Growing in faith is not piling up intellectual certainties nor forcing oneself to “believe very hard”: it is letting the theological virtue grow within us by which the intellect adheres, under the attraction of grace, to God who reveals himself, and by which the whole soul entrusts itself to him. Christian faith is not a probable opinion we would hold “by default”: it is firm adherence to a God who speaks, founded not on the strength of our reasoning, but on the authority of him who “can neither deceive nor be deceived”[1].
It is the first of the three theological virtues, and the root of the other two: without faith, hope has no object and charity has no face. Yet it is a virtue we readily suppose to be acquired once and for all, whereas it is received, kept, nourished — and can be lost. The saints never spoke of it as something settled: they lived it as a light that shines in the night, “a way of possessing what we hope for, a means of knowing realities we do not see” (Heb 11:1)[2].
This article is devoted to the practical path: how faith grows, by what means, and by avoiding which pitfalls — doubt and unbelief on one side, dead faith and false assurance on the other. For the saints’ own voice on this theme, see the anthology What the Saints Say About Faith. For common misunderstandings — faith confused with a feeling, a cultural heritage or mere intellectual assent — see Common Errors Concerning Faith. For the other two theological virtues, see How to Grow in Hope and How to Grow in Charity. For the filial aspect of trust and abandonment that prolongs faith, see How to Grow in Trust and How to Grow in Abandonment to God.
Why Seek to Grow in Faith?
The Virtue That Bears the Other Two
Faith is the first of the three theological virtues, not by dignity — charity is the greatest (1 Cor 13:13) — but by order of generation: we first believe, then hope for what we have believed, then love what we hope for. Saint Paul names them in this foundational order, and Saint Augustine saw in them a building, the house of God: “credendo fundatur, sperando erigitur, diligendo perficitur” — it is by believing that it is founded, by hoping that it rises, by loving that it is completed[3]: faith is the foundation, hope the walls that rise, charity the roof that crowns. The Book of Heaven likewise places faith among the three roots of the tree of virtues:
“My most dear daughter, the three roots of the trunk of the tree are Faith, Hope and Charity. […] It is to say, then, that Faith, Hope and Charity encompass everything and are the foundation of the tree which can produce nothing without them.” — Jesus to Luisa Piccarreta, The Book of Heaven, vol. 2, 9 September 1899[4]
To neglect faith, therefore, is to undermine the whole building. A hope without faith no longer expects anything definite; a charity without faith shrinks to philanthropy. To grow in faith is to strengthen the root from which everything else draws its sap.
“Without Faith It Is Impossible to Be Pleasing to God”
Faith is not an ornament of the Christian life: it is the condition of entry. The Letter to the Hebrews states it bluntly:
“Now, without faith it is impossible to be pleasing to God; for whoever would draw near to him must believe that he exists and that he rewards those who seek him.” — Letter to the Hebrews 11:6[5]
The whole spiritual life begins there. “He who is righteous by faith shall live” (Rom 1:17, citing Hab 2:4), Saint Paul repeats[6] : faith is not only the starting point, it is the vital environment in which the Christian breathes and advances. It is by faith that we gain access to grace (Rom 5:1-2), by faith that we are justified, by faith that we stand firm. The Catechism recalls that faith is “the beginning of eternal life”, already begun in us[7]. To grow in faith, therefore, is to make that very life grow within us.
What Holds Firm in the Night
The most existential reason to cultivate faith is that it is what holds when everything else falters. Faith sees in the dark what the eye does not see; it gives meaning to trial, a support where evidence fails. Yet the Catechism warns that it is never secure:
“Faith is an entirely free gift that God makes to man. This priceless treasure, we can lose it. […] To live, grow and persevere in the faith until the end we must nourish it with the word of God; we must beg the Lord to increase it […] ; it must ‘be working through charity.’” — Catechism of the Catholic Church, § 162[8]
This single paragraph already contains the whole practical program of this article: faith is nourished, asked for, and works through charity. A faith left fallow withers; a faith cultivated becomes the light that passes through nights.
Understanding What We Seek to Acquire
Before the means, a decisive clarification: many fail to grow in faith because they aim at a counterfeit. It is confused with a religious feeling, with an inherited opinion, with a temperamental certainty. The theological virtue of faith is something else entirely, and to define it exactly is already half the journey.
A Theological Virtue, Not an Opinion or a Feeling
The Catechism gives the canonical definition, which must be meditated word for word:
“Faith is the theological virtue by which we believe in God and believe in all that he has said and revealed to us, and that Holy Church proposes for our belief, because he is truth itself.” — Catechism of the Catholic Church, § 1814[9]
Three features separate it from a mere opinion. First, its object: not an idea, but “God and all that he has revealed” — a Person who speaks. Next, its motive: we believe “because he is truth itself”, not because the thing appears evident or plausible to us. Faith, therefore, is not a chain of reasoning that would end in God, but an adherence to the word of God; as the First Vatican Council says, the Church professes that faith is “a supernatural virtue by which, forestalled by God and aided by grace, we believe to be true the things he has revealed to us, not because of their intrinsic truth perceived by the natural light of reason, but because of the authority of God himself who reveals”[10]. Finally, its rule: “what Holy Church proposes for our belief” — for we do not believe a do-it-yourself private revelation, but the faith of the Church, received and handed on. This is why faith can be more certain than any human knowledge, “because it is founded on the very word of God who cannot lie”[11], while remaining obscure, since it adheres to realities it does not yet see.
To Believe God on His Word, to Believe God, to Believe into God
Saint Thomas Aquinas, taking up a distinction of Saint Augustine, considers the one act of faith under three aspects in relation to its object (Summa Theologiae, II-II, q. 2, a. 2) — three formulas which the French translation renders as “croire à Dieu”, “croire Dieu” and “croire en Dieu” (translation followed throughout this article: Éditions du Cerf)[12] :
- To believe God (credere Deo): to adhere to what God says, because of him who says it — the formal reason of faith: the First Truth to which we adhere in order to hold all the rest.
- To believe God (credere Deum): to attach oneself to God himself as the material object of faith: nothing is proposed to us for belief, except insofar as it concerns God.
- To believe into God (credere in Deum): the intellect, moved by the will, moves toward God as toward its end, for the First Truth offers itself to the will as an end. That this movement is a movement of love toward the Person is Saint Augustine's reading (Tractate 29 on the Gospel of John): the demons themselves believe God, without believing into him.
This distinction is golden for practical life. One can hold exact truths (believing God) without one's whole being tending toward him (believing into him). To grow in faith is to let the one act of faith deepen under its three aspects at once: adhering to the word heard, attaching oneself to the First Truth, tending with one's whole being toward God who is loved. Saint Thomas sums up this fullness in a magnificent formula: faith is “the habit of the mind whereby eternal life begins in us, and which makes the intellect assent to what does not appear”[13].
Dead Faith and Living Faith
Hence the most practical distinction of all: there is a dead faith and a living faith. One can possess faith as a truth held, but without the charity that makes it live — Saint Thomas calls it “unformed faith” (fides informis), true faith but without its soul[14]. Living faith, by contrast, is “formed by charity” (fides formata), and it alone saves. Saint James hammers the point:
“So then, faith by itself, if it has no works, is dead. […] So, as the body deprived of breath is dead, so faith without works is dead.” — Letter of Saint James 2:17,26, official liturgical translation (AELF)[15]
And Saint Paul sums it up in a word that will be the heart of the practical section: what counts is “faith which acts through charity” (Gal 5:6, official liturgical translation — AELF)[16]. To grow in faith, therefore, is never merely to believe more things: it is to let faith descend into life, down to hands and heart.
A Gift First Received
A decisive truth, and the most consoling: faith is not a conquest of our intelligence. It is an infused virtue, poured into the soul with grace, which we do not manufacture but receive. When Peter confesses Jesus as “the Christ, the Son of the living God”, the Lord immediately answers him:
“Blessed are you, Simon son of Jonah! For flesh and blood has not revealed this to you, but my Father in heaven.” — Gospel according to Saint Matthew 16:17[17]
The Catechism draws the rule from it: “faith is a gift of God, a supernatural virtue infused by him”[18]. Saint Paul says it bluntly: “For by grace you have been saved, and through faith. This is not from you, it is the gift of God” (Eph 2:8)[19]. The practical consequence is immense: since faith is first received, the first means of growing is not effort, but asking. We will return to this.
“I Believe So That I May Understand”: Faith and Reason
It remains to dispel a tenacious misunderstanding: that believing would not be reasonable. Yet faith does not humiliate intelligence; it raises it. Far from opposing reason, it precedes it in order to open it. Saint Augustine struck the founding formula:
“Believe so that you may understand. […] Understand to believe my word; believe to understand the word of God.” — Saint Augustine, Sermon 43[20]
Saint Anselm made it the program of all theology — fides quaerens intellectum, “faith seeking understanding”: “For I do not seek to understand so that I may believe, but I believe so that I may understand”[21]. The Catechism takes up this balance: faith “seeks understanding”, and “the grace of faith opens the eyes of the heart” to a deeper intelligence of the mystery[22]. To grow in faith, therefore, is not to give up thinking: it is to think from a light received. Faith lays the foundations on which reason can build higher than it would go alone.
The Two Enemies of Faith
Faith has two enemies, which ruin it each in its own way. On one side, voluntary doubt and unbelief, which withdraw assent and cease to believe; on the other, dead faith and false assurance, which keep the word of faith but have lost its life, for lack of charity and works. Knowing them protects growth, for one can lose faith through one as through the other. They are not two symmetrical “excesses” around it: Saint Thomas teaches that toward God, who is the object of the theological virtues, one cannot sin by excess — one never believes too much — and that the good of these virtues does not consist in a mean (Summa, I-II, q. 64, a. 4). Dead faith, therefore, is not an overflow of faith: it is a faith deprived of the charity that makes it living (II-II, q. 4, a. 3-4).
Doubt and Unbelief: Ceasing to Believe
The first enemy attacks assent itself. The Catechism first distinguishes voluntary doubt from involuntary trial:
“Voluntary doubt concerning faith disregards or refuses to hold as true what God has revealed and the Church proposes for belief. Involuntary doubt designates hesitation in believing, difficulty in overcoming objections connected with faith, or again anxiety caused by the obscurity of faith.” — Catechism of the Catholic Church, § 2088[23]
The distinction is crucial and frees many scrupulous souls: difficulty is not doubt. Feeling objections, passing through darkness, being assailed by questions is not a sin — it is often the very place where faith is purified. Saint John Henry Newman put it in a celebrated phrase: “Ten thousand difficulties do not make one doubt”[24]. Sin begins when one deliberately cultivates refusal, when one nurtures suspicion out of laziness or comfort. Pushed to the end, this refusal becomes unbelief, heresy, apostasy or schism — the four direct sins against faith distinguished by the Catechism[25].
Dead Faith and False Assurance: Believing Without Living
The opposite enemy is more subtle, because it keeps the appearances of faith. It is dead faith: one holds the truths, recites the Creed, calls oneself a believer — but nothing in life bears its mark. “You, you believe that there is one God. Very well! But the demons too believe it and they tremble” (Jas 2:19, official liturgical translation — AELF)[26] : assent alone does not save. Added to this sterility is a false assurance, akin to the presumption that threatens hope: to consider oneself firm in faith without ever nourishing or exercising it, to presume that one will keep it without struggle. Yet “let him who thinks he stands take heed lest he fall” (1 Cor 10:12, official liturgical translation — AELF). Peter, the most confident, denied three times. Faith that is not nourished, not humbled, not exercised, dries up from within without being noticed — until the day of trial when one discovers that only a word remained.
A Living and Humble Faith
In face of these two enemies, faith is kept by a threefold fidelity, which can be summed up thus: firm in adherence, humble in seeking, living in works. It adheres without reserve, because it rests on God and not on evidence; but it remains humble, for it knows that “at present we see indistinctly, as in a mirror” (1 Cor 13:12, official liturgical translation — AELF), and that it “still seeks to understand”; and it works through charity, for a faith that does not translate into deeds is but a corpse. The following table fixes this discernment.
| Doubt / Unbelief | Living Faith | Dead Faith / False Assurance | |
|---|---|---|---|
| Error | One withdraws assent | Firm adherence and life according to faith | One keeps the word of faith without living or defending it |
| About God | One doubts his word | One relies on his Truth | One settles for an abstract God |
| About oneself | One relies on one's own reason alone | One receives faith and exercises it | One thinks oneself secure without effort |
| Fruit | Anxiety, cooling, rupture | Light, courage, charity in action | Lukewarmness, sterility, collapse at trial |
Reading the table: living faith is not a fragile point between two dangers, but a fullness that holds together what each deviation separates — firm adherence to the word of God and a life that embodies it. We grow in faith by pushing back both enemies at once.
Concrete Means to Grow in Faith
Here is the practical heart of this article. The spiritual masters and the Catechism itself have not merely praised faith: they have indicated precise, repeatable means, within everyone's reach. They can be grouped into a few major areas, which take up one by one the verbs of § 162: to nourish, to ask, to make it work through charity.
Asking for Faith as a Grace
The first and most decisive means: since faith is an infused gift, we do not manufacture it; we ask for it. The Apostles themselves, who saw Christ, asked him for the essential:
“Increase our faith!” — Gospel according to Saint Luke 17:5[27]
And the father of the epileptic boy found the prayer of all imperfect believers, which says at once faith and its weakness:
“I believe; help my unbelief!” — Gospel according to Saint Mark 9:24[28]
To often repeat an act of faith — “My God, I firmly believe all the truths you have revealed and that you teach us through your Church, because you can neither deceive nor be deceived” — is not a pious formula: it is the very exercise of the virtue, which makes it grow each time we make it. To ask for it is already to exercise it.
Listening to and Meditating on the Word of God
Faith has an ordinary origin: hearing the Word. Saint Paul fixed its law:
“Now faith comes from what is heard; and what is heard is the word of Christ.” — Letter to the Romans 10:17, official liturgical translation (AELF)[29]
“Fides ex auditu”: we truly believe only what we have long listened to. Reading and meditating on Scripture, frequenting the Gospels — “ignorance of Scripture is ignorance of Christ,” said Saint Jerome[30]. The more the Word dwells in memory and heart, the more faith has matter in which to take root; a faith that is never nourished by the Word floats without content. This is the first of the three verbs of § 162: “to nourish faith with the word of God.” On the prayerful reading of Scripture, see How to Grow in Lectio Divina.
Professing and Confessing One's Faith
Faith received wants to be spoken. The “I believe” of the Creed is not an opinion kept to oneself: it is a profession that commits and strengthens. “For it is with the heart that one believes unto righteousness, it is with the mouth that one confesses faith unto salvation” (Rom 10:10, official liturgical translation — AELF)[31]. To recite the Creed attentively, to ponder it article by article, is to regain a foothold on the rock of the Church's faith. The Catechism recalls that “to believe” is both a personal and an ecclesial act: “No one has given himself faith as no one has given himself life. The believer has received faith from others, he must hand it on to others”[32]. To profess one's faith publicly, even when it costs, is one of the acts that most strengthens it.
Nourishing Faith Through the Sacraments
Faith is not nourished by thoughts alone: it has its sacraments. Baptism is “the sacrament of faith” (CCC § 1253); the Eucharist is “the mystery of faith” par excellence, where one adheres, against all sensible evidence, to the real presence of Christ. Before the host, faith is challenged and grows in proportion: “Adoro te devote, latens Deitas,” prayer attributed to Saint Thomas — “Devoutly I adore thee, hidden Deity”[33]. Confession, for its part, raises up faith weakened by sin, for sin darkens the believer's gaze. To receive Communion, to adore, to go to confession is to stand at the sources where faith is revived. See How to Grow in Frequent Communion and How to Grow in Regular Confession.
Making Faith Work Through Charity
The third verb of § 162, and the most neglected: faith must “be working through charity.” A faith that does not translate into acts of charity remains “dead” (Jas 2:26). Conversely, each act of charity strengthens faith, because it makes it pass into life, where it takes flesh. Serving the poor, forgiving, fulfilling one's duties of state out of love is believing with one's hands. This is why growing in faith and growing in charity are not two separate projects: “faith working through love” is a single life. See How to Grow in Charity.
Deepening and Studying the Faith
Faith “seeks understanding” (CCC § 158): to leave it ignorant is to expose it. Many doubts are only misunderstandings that a little study would dispel. Deepening the Catechism, reading the Fathers, frequenting the great doctors is to give faith the intelligence that defends and unfolds it. This work is not reserved to clerics: every believer must be able to “give a reason for the hope that is in you” (1 Pet 3:15, official liturgical translation — AELF)[34]. An instructed faith resists where a sentimental faith yields at the first shock. But this study bears fruit only in humility of heart, never in proud curiosity: see How to Grow in Humility.
Persevering in Night and Trial
Faith is forged above all in the fire of trial. It is in the night that it becomes pure; in days of consolation, we do not know whether we truly believe or only enjoy the light. Saint John of the Cross teaches that faith is precisely the dark path of union with God:
“For faith alone is a proximate and proportionate means for uniting the soul to God.” — Saint John of the Cross, The Ascent of Mount Carmel, Book II[35]
He describes it as a night for the understanding: it unites us to God by depriving us of sensible lights, so that we lean on him alone. Saint Thérèse of the Child Jesus, in her terrible “night of faith” begun at Easter 1896 — about eighteen months before her death —, no longer enjoyed any sensible certainty of Heaven — and it is there that she believed the most:
“I think I have made more acts of faith in this past year than in all my life before. […] I run to my Jesus, I tell Him I am ready to shed even the last drop of my blood to confess that there is a Heaven.” — Saint Thérèse of the Child Jesus, Manuscript C[36]
The darker the trial, the purer the act of faith, for it no longer rests on anything felt — only on God. It is the faith of Abraham “hoping against hope” (Rom 4:18), the one that holds when everything invites letting go. See How to Grow in Perseverance.
The Fruits of a Growing Faith
How can we tell that we are truly growing in faith? Not by a feeling, but by stable fruits that the saints and the Catechism describe with constancy.
Light and Certainty
The first fruit is an interior light: faith makes us see reality differently, in God's perspective. This is the whole meaning of the image the Church has always associated with faith, taken up by the encyclical Lumen fidei:
“The light of faith (Lumen Fidei): With this expression, the tradition of the Church has designated the great gift brought by Jesus. […] Faith is born of the encounter with the living God, who calls us and reveals his love to us.” — Pope Francis, Lumen fidei, §§ 1 and 4[37]
This light does not dazzle, but it orients. It gives faith a certainty of a unique kind: not the evidence of a demonstration, but the assurance of one who trusts the word of a friend who does not lie. “Faith is certain, more certain than all human knowledge, because it is founded on the very word of God” (CCC § 157). To grow in faith is to see the world, trial and death in this light.
The Courage to Bear Witness
Second fruit: faith makes us courageous. Whoever truly believes cannot remain silent: faith impels us to bear witness, to confess, to “give an account” of what makes us live. The whole line of martyrs was born of this — the faith of the martyrs, whose blood is “the seed of Christians,” in Tertullian's words[38]. A growing faith makes us missionary, because it cannot keep to itself the light received. Thus it joins hope and charity, its two sisters, in the single momentum of proclamation.
Peace and Union with God
Third fruit: faith leads to union with God, of which it is, according to Saint John of the Cross, the proximate and proportionate means. From this union is born a peace that circumstances cannot shake, because it rests not on them but on God held to be faithful. Living faith thus opens naturally onto trust and abandonment, where the believer places himself in the hands of him whom he has believed. See How to Grow in Trust and How to Grow in Abandonment to God.
Faith in the Divine Will
The spirituality of the Divine Will, handed on to the Servant of God Luisa Piccarreta (1865-1947), gives faith its final accent. In simple words: the Divine Will is the very life of God, offered to whoever truly desires it. Doing God's will — obeying him — keeps two wills face to face: mine, which I submit, and his, which I follow. Living in the Divine Will is more: my will effaces itself to let his act in me, like a child carried by his father. We no longer merely do what God commands: we live of his life. In her writings, faith is not a mere assent of the intelligence: Jesus says to her “Faith is God”, and Luisa explains that it “helps keep eyes fixed on the Supreme Being”, and that “Faith is like a king in the midst of his court” whom all the other virtues surround and serve[39] — the first of the three roots that bear the whole tree of virtues.
As we have seen, it is Jesus who places faith among the three roots of the tree of virtues, and who names it first (vol. 2, 9 September 1899)[40]. The article sees in this the very order of the theological virtues: it is through faith that the soul knows God, without which neither hope nor charity would have an object (cf. Saint Thomas, Summa, I-II, q. 62, a. 4). To grow in faith, from this perspective, is to learn to look at everything — joy as well as trial — recognizing in all God's hand and his will. Faith then becomes the threshold of “life in the Divine Will”: we no longer merely believe truths about God, we begin to see and to live as God wills, in an adherence that is no longer only of the intelligence, but of the whole being surrendered to him.
Mary, the First in Faith
We do not grow in a virtue by fixing it as an abstract ideal, but by contemplating those who have lived it perfectly. Yet faith has a sovereign mistress.
Elizabeth greets her as the believer par excellence:
“Blessed are you who believed that what was spoken to you by the Lord would be fulfilled!” — Gospel according to Saint Luke 1:45[41]
At the Annunciation, Mary made the purest act of faith in all history: “Let it be done to me according to your word” (Lk 1:38). The Catechism says of her that she “realizes in the most perfect way the obedience of faith”[42]. And the Second Vatican Council recalls that she “advanced in her pilgrimage of faith, faithfully keeping union with her Son unto the cross”[43], where she believed when all seemed lost — the dawn of Easter before the dawn. To take Mary as mistress of faith is to learn to say “fiat” to the word we do not yet understand, to believe in the night of Holy Saturday, to let God accomplish what he has said. To grow in faith, in the end, is to become, under her gaze, a believer who walks “in faith, not by clear vision” (2 Cor 5:7)[44] — until the day when faith will give way to vision, and we shall see “face to face” (1 Cor 13:12) him whom we have believed without seeing.
A Concrete Path, Day by Day
Faith does not grow through great resolutions, but through small and repeated fidelity. The means studied can be summed up in a simple program, graduated from the most accessible to the most demanding:
| Frequency | Exercise of faith | What it trains |
|---|---|---|
| Every day | Make an act of faith: “My God, I believe in you” | Faith as gift received and exercised |
| Every day | Read and meditate on a passage of Scripture | Fides ex auditu: nourishing faith |
| Often | Recite the Creed attentively | The profession that strengthens |
| Regularly | Receive Communion, adore, go to confession | The sacraments of faith |
| Daily | Translate faith into an act of charity | “Faith working through love” |
| Regularly | Deepen a point of doctrine | The intelligence of faith |
| In trial | Renew the act of faith “against all evidence” | Faith purified by night |
Reading the table: none of these exercises is spectacular; it is their faithful repetition that transforms. Start with one or two, keep them, then add more.
The essential thing is not to aim at faith in general, but to make, today, the concrete act that presents itself: this page of the Gospel to meditate, this doubt not to be cultivated, this gesture of charity where we believe with our hands, this darkness to be crossed without letting go. For faith is the lamp of the traveler; and as long as night lasts, it is she who lights the steps. “We walk in faith, not by clear vision” (2 Cor 5:7): it suffices, each day, to take one step — until the homeland where we shall no longer believe, because we shall see.
To Go Further
- What the Saints Say About Faith — an anthology of the great words of saints, doctors and mystics on this virtue and on adherence to God who reveals himself.
- Common Errors Concerning Faith — misunderstandings to avoid: faith confused with a feeling, a cultural heritage or mere intellectual assent.
- How to Grow in Hope and How to Grow in Charity — the other two theological virtues, sisters of faith.
- How to Grow in Trust and How to Grow in Abandonment to God — the filial face that prolongs faith into the surrender of the whole being to God.
- How to Grow in Lectio Divina — the prayerful reading of Scripture, the first nourishment of faith.
- How to Grow in Perseverance — the virtue of endurance, without which faith does not hold to the end.
Notes and References
Catechism of the Catholic Church, § 156. Official French edition, Mame/Plon, 1992. We believe “because of the authority of God himself who reveals and who can neither deceive nor be deceived”; “Nevertheless, so that the homage of our faith might be in accordance with reason, God willed that the interior helps of the Holy Spirit be accompanied by exterior proofs of his Revelation” (miracles, prophecies). That faith is “a supernatural gift of God” is taught by § 179.
1Letter to the Hebrews 11:1, official liturgical translation (AELF): “Faith is a way of possessing what we hope for, a means of knowing realities we do not see.” Cited in CCC § 146 (in the Catechism's own translation: “the assurance of things hoped for, the conviction of things not seen”).
2Saint Augustine (354-430), Sermon 27 (serm. XXVII, on Ps 95 and Rom 9 — listed “de verbis Apostoli” in older editions, whose numbering varies by edition; passage cited by Saint Robert Bellarmine, On Justification, I, 13): “Cantando aedificatur, credendo fundatur, sperando erigitur, diligendo perficitur” — it is built by singing, founded by believing, raised by hoping, completed by loving.
3Jesus to Luisa Piccarreta (1865-1947), The Book of Heaven, vol. 2, 9 September 1899 (Fr. ed. GE – La Volonté Divine – Lumen Luminis, “for private use”, pp. 95-96): “My most dear daughter, the three roots of the trunk of the tree are Faith, Hope and Charity. […] It is to say, then, that Faith, Hope and Charity encompass everything and are the foundation of the tree which can produce nothing without them.” That day, Luisa sees coming from the wounded Heart of Jesus a tree trunk with three roots entering her own, bearing branches, flowers, fruits, pearls and precious stones. Luisa understands that the flowers represent the virtues, the fruits the sufferings, and the pearls and precious stones the sufferings lived out of pure love for God.
4 40Letter to the Hebrews 11:6, official liturgical translation (AELF): “Now, without faith it is impossible to be pleasing to God; for whoever would draw near to him must believe that he exists and that he rewards those who seek him.”
5Letter to the Romans 1:17, citing Habakkuk 2:4, official liturgical translation (AELF): “He who is righteous by faith shall live.” Foundational verse of the Pauline doctrine of justification, taken up in Gal 3:11 and Heb 10:38.
6Catechism of the Catholic Church, § 163, citing Saint Basil and Saint Thomas: “Faith makes us taste in advance, as it were, the joy and the light of the beatific vision”; it is “the beginning of eternal life.”
7Catechism of the Catholic Church, § 162, citing 1 Tim 1:18-19 and Gal 5:6. Faith is a gift that can be lost; to keep it, it must be nourished by the Word, we must ask God to increase it, and make it “work through charity.”
8Catechism of the Catholic Church, § 1814. Canonical definition of faith as a theological virtue; § 143 adds: “By faith, man submits his intellect and will completely to God.”
9First Vatican Council, dogmatic constitution Dei Filius (1870), ch. 3, De fide (Denzinger-Hünermann 3008): “Since man depends totally on God as his creator and Lord, and created reason is wholly subject to uncreated Truth, we are bound to offer to God who reveals himself the full submission of our intellect and will by faith. This faith […] the Catholic Church professes to be a supernatural virtue by which, forestalled by God and aided by grace, we believe to be true the things he has revealed, not because of their intrinsic truth perceived by the natural light of reason, but because of the authority of God himself who reveals, who can neither deceive nor be deceived.” (French trans. Documenta Catholica Omnia, after the Enchiridion Symbolorum).
10Catechism of the Catholic Church, § 157: “Faith is certain, more certain than all human knowledge, because it is founded on the very word of God who cannot lie.”
11Saint Thomas Aquinas (1225-1274), Summa Theologiae, II-II, q. 2, a. 2, taking up Saint Augustine (De verbis Domini, serm. 61; In Ioannis Evangelium, tract. 29 — the two passages alleged by Thomas in the sed contra): credere Deo (“believing God”: the formal reason, the First Truth to which we attach ourselves), credere Deum (“believing God”: the material object, all that is proposed to us for belief insofar as it concerns God), credere in Deum (“believing into God”: the intellect, moved by the will, moves toward God as toward its end); “by these three expressions we designate not different acts of faith, but one and the same act having different relations to the object of faith” (ad 1). That this last movement is a movement of love toward the Person is the reading of Saint Augustine, Tractate 29 on the Gospel of John: the demons themselves believe God, without believing into him. French translation followed here: Summa Theologiae, Éditions du Cerf.
12Saint Thomas Aquinas, Summa Theologiae, II-II, q. 4, a. 1, taking up Heb 11:1: faith is “the habit of the mind whereby eternal life begins in us, making the intellect assent to what does not appear” (habitus mentis, qua inchoatur vita aeterna in nobis, faciens intellectum assentire non apparentibus).
13Saint Thomas Aquinas, Summa Theologiae, II-II, q. 4, a. 3-4: “unformed” faith (fides informis), without charity, is true but imperfect and dead faith; faith “formed” by charity (fides formata) is living and meritorious faith. Cf. CCC § 1815.
14Letter of Saint James 2:17,26, official liturgical translation (AELF): “So then, faith by itself, if it has no works, is dead. […] So, as the body deprived of breath is dead, so faith without works is dead.”
15Letter to the Galatians 5:6, official liturgical translation (AELF): “For in Christ Jesus, what has value is not whether one is circumcised or not, but faith which acts through charity” (fides quae per caritatem operatur). Key verse for articulating faith and works; cited in CCC §§ 1814 and 162.
16Gospel according to Saint Matthew 16:16-17, official liturgical translation (AELF): at Peter's confession, Jesus answers that it is not “flesh and blood” but the Father who revealed it to him. Cited in CCC §§ 153 and 442 to show that faith is a gift.
17Catechism of the Catholic Church, § 153: “Faith is a gift of God, a supernatural virtue infused by Him. […] To lend this faith, man needs the prevenient and helping grace of God, as well as the interior helps of the Holy Spirit.”
18Letter to the Ephesians 2:8-9, official liturgical translation (AELF): “For by grace you have been saved through faith, and this is not your own doing; it is the gift of God — not the result of works, so that no one may boast.”
19Saint Augustine (354-430), Sermon 43, 7, 9: “Intellige ut credas, crede ut intelligas” — “Understand so that you may believe, believe so that you may understand.” Augustine articulates faith and reason: faith precedes understanding of the mystery without excluding it. Cf. CCC § 158.
20Saint Anselm of Canterbury (1033-1109), Proslogion, ch. 1: “Neque enim quaero intelligere ut credam, sed credo ut intelligam” — “For I seek not to understand that I may believe, but I believe that I may understand.” Origin of the formula fides quaerens intellectum (faith seeking understanding).
21Catechism of the Catholic Church, § 158, citing Saint Anselm and Saint Augustine: “‘Faith seeks understanding’: it is inherent to faith that the believer desires to know better Him in whom he has put his faith, and to understand better what He has revealed.” The grace of faith opens “the eyes of the heart” (Eph 1:18).
22Catechism of the Catholic Church, § 2088: “Voluntary doubt concerning faith disregards or refuses to hold as true what God has revealed and the Church proposes for belief. Involuntary doubt designates hesitation in believing, difficulty in overcoming objections connected with faith, or again anxiety caused by the obscurity of faith.” Essential distinction between voluntary doubt (deliberate refusal, which is a sin) and involuntary doubt (hesitation, difficulty, anxiety in face of the obscurity of faith, which is not).
23Saint John Henry Newman (1801-1890), Apologia pro vita sua (1864): “Ten thousand difficulties do not make one doubt” — “Ten thousand difficulties do not make one doubt.” Newman, canonized by Pope Francis on 13 October 2019 then proclaimed Doctor of the Church by Pope Leo XIV on 1 November 2025 (All Saints' Day Mass), distinguishes intellectual difficulty, compatible with firm faith, from doubt, which is refusal to adhere. English original in the note; French translation in the body.
24Catechism of the Catholic Church, § 2089: definition of direct sins against faith — unbelief (neglect of revealed truth or refusal to assent to it), heresy (obstinate denial of a truth to be believed with divine and catholic faith), apostasy (total repudiation of the faith) and schism (refusal of submission to the Pope or of communion).
25Letter of Saint James 2:19, official liturgical translation (AELF): “You, you believe that there is one God. Very well! But the demons too believe it and they tremble.” Intellectual assent alone does not suffice for salvation.
26Gospel according to Saint Luke 17:5, official liturgical translation (AELF): “The apostles said to the Lord, ‘Increase our faith!’” Faith is asked for, even by those who already believe.
27Gospel according to Saint Mark 9:24, official liturgical translation (AELF): “Immediately the father of the child cried out, ‘I believe; help my unbelief!’” Model prayer of the believer aware of the weakness of his faith.
28Letter to the Romans 10:17, official liturgical translation (AELF): “Now faith comes from what is heard; and what is heard is the word of Christ” (fides ex auditu). Foundation of the need to listen to and meditate on the Word in order to grow in faith.
29Saint Jerome (c. 347-420), Commentary on Isaiah, prologue: “Ignorance of Scripture is ignorance of Christ.” Cited in CCC § 133 and in the conciliar constitution Dei Verbum, § 25.
30Letter to the Romans 10:10, official liturgical translation (AELF): “For it is with the heart that one believes unto righteousness, it is with the mouth that one confesses faith unto salvation.”
31Catechism of the Catholic Church, § 166: “Faith is a personal act: the free response of the human person to the initiative of God who reveals himself. But faith is not an isolated act. […] The believer has received faith from others and should hand it on to others.”
32Prayer Adoro te devote (attributed to Saint Thomas Aquinas, c. 1264, at the time of the institution of Corpus Christi; not integrated into the liturgical office, probably for private use): “Adoro te devote, latens Deitas” — “Devoutly I adore thee, hidden Deity.” The prayer is an act of faith in the real presence, where “sight, touch, taste are deceived; but hearing alone safely believes.”
33First Letter of Saint Peter 3:15, official liturgical translation (AELF): “Be ready at any moment to offer a defense before anyone who asks you for a reason for the hope that is in you.” Foundation of the duty to instruct and defend one's faith.
34Saint John of the Cross (1542-1591), The Ascent of Mount Carmel, Book II, chapter IX (“How faith is to the intellect a proximate and proportionate means for raising the soul to divine union”, French trans. Abbé Jean Maillart, text verified word for word in the digital ed. abbaye-saint-benoit.ch / jesusmarie.com after Maillart): “for faith alone is a proximate and proportionate means for uniting the soul to God, since there is no other difference, except that God is seen either clearly by the beatific vision, or obscurely by the lights of faith.”
35Saint Thérèse of the Child Jesus (1873-1897), Autobiographical Manuscripts, Manuscript C (written in June 1897; transcription available at the Archives of the Carmel of Lisieux, https://archives.carmeldelisieux.fr/archive/manuscrit-c/): account of the trial of faith. “I think I have made more acts of faith in this past year than in all my life before. […] I run to my Jesus, I tell Him I am ready to shed even the last drop of my blood to confess that there is a Heaven.”
36Pope Francis, encyclical letter Lumen fidei (29 June 2013), §§ 1 and 4. Encyclical begun by Benedict XVI and completed by Francis: § 1: “The light of faith (Lumen Fidei): With this expression, the tradition of the Church has designated the great gift brought by Jesus”; § 4: “Faith is born of the encounter with the living God, who calls us and reveals his love to us, a love that precedes us and on which we can lean to be solid and build our life.” Full text on Vatican.va.
37Tertullian (c. 155-220), Apologeticum, ch. 50, § 13: “The blood of Christians is seed” (semen est sanguis christianorum), often quoted as “the blood of martyrs is the seed of Christians.” Witness to the fruitfulness of faith confessed unto martyrdom.
38Jesus to Luisa Piccarreta, The Book of Heaven, vol. 2, entry of 28 February 1899 (Fr. ed. GE – La Volonté Divine – Lumen Luminis, “for private use”, pp. 6-8). Luisa, whose confessor asked her to write on faith according to what Jesus taught her, receives this word: “Faith is God.” Luisa explains: “I understood that faith is God himself. […] It helps it keep eyes fixed on the Supreme Being so that it learns nothing of things here below, except through God”; “Faith is like a king in the midst of his court: all the other virtues surround and serve it. Without Faith, the other virtues are lifeless.”
39Gospel according to Saint Luke 1:45, official liturgical translation (AELF): “And blessed are you who believed that there would be a fulfillment of what was spoken to you from the Lord.” Word of Elizabeth at the Visitation, first beatitude of the Gospel, addressed to Mary's faith.
41Catechism of the Catholic Church, § 148: “The Virgin Mary realizes in the most perfect way the obedience of faith”; § 149: “During her whole life, and up to her last ordeal, when Jesus her son died on the cross, her faith did not waver”; the Church venerates in Mary “the purest realization of faith.”
42Second Vatican Council, dogmatic constitution Lumen gentium (1964), § 58: “Thus the Blessed Virgin advanced in her pilgrimage of faith, faithfully keeping union with her Son unto the cross where, not without a divine plan, she stood.” Cf. John Paul II, encyclical Redemptoris Mater (1987), on Mary's “pilgrimage of faith.”
43Second Letter to the Corinthians 5:7, official liturgical translation (AELF): “for we walk by faith, not by sight.” The condition of the believer on earth, until the beatific vision where faith will give way (1 Cor 13:12).
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