Why does Advent exist?

Before being a season of the calendar, Advent is a word — and that word already carries its whole reason for being. To understand it is to understand why this season exists.

Adventus: coming, advent, parousia

The English Advent comes from the Latin adventus, a noun derived from the verb advenire, "to come towards, to arrive". In classical Latin, the adventus meant the solemn arrival of an important person — an emperor, a magistrate — in a city that awaited him and received him in procession^[4]. Christians took up this word to translate the Greek parousia, the New Testament term for the glorious coming of Christ at the end of time^[5]. Adventus and parousia are thus, originally, two words for awaiting a king.

The choice of vocabulary is therefore not neutral. In calling this season adventus, the Church does not merely say "here is the before-Christmas": she says "here is the time when we await the King's coming". And since Christ comes in two ways — already come in the flesh, still awaited in glory — the word covers from the outset the two advents that structure the whole spirituality of Advent.

A name that is already a programme

From this name follows directly the nature of Advent: a season not of feasting, but of watchful waiting. We only wait well for what we desire; and we only truly desire what we wait for. Advent exists to reopen, each year, that desire which habit dulls. The Catechism puts it plainly:

"When the Church celebrates the liturgy of Advent each year, she makes present this ancient expectancy of the Messiah, for by sharing in the long preparation for the Saviour's first coming, the faithful renew their ardent desire for his second coming." — Catechism of the Catholic Church, § 524^[6]

The whole of Advent holds in that verb: to renew desire. The liturgical season adds no new event to history; it makes the Church contemporary with Israel's expectation, so that she in turn may await Christ's return with the same fervour. Advent is, literally, a school of desire for God.

Why "Advent" is not "before"

The confusion between Advent and before (in French, Avent and avant, which sound almost alike) is so common that it deserves to be cleared up. The two words have no connection: before comes from Old English beforan, while Advent comes from adventus ("coming")^[7]. To confuse them is to reduce Advent to an interval — the time before Christmas — whereas it is a presence on the way: the coming of the One we await. The nuance is spiritual as much as linguistic: Advent is not defined by what follows it, but by Him whom it announces.

If we understand the name, the underlying question remains: why institute a whole season for waiting? The answer lies in the very way Christ "comes". He does not come once, but in several registers; and Advent exists to hold them together.

The twofold coming: Christmas and the end of time

The heart of Advent is its twofold gaze. It is the dominant note of the liturgical books, which open their definition of the season with this duality:

"Advent has a twofold character: as a season to prepare for Christmas when Christ's first coming to us is remembered; as a season when that remembrance directs the mind and heart to await Christ's Second Coming at the end of time." — Universal Norms on the Liturgical Year and the Calendar, no. 39^[8]

This twofold character explains the inner architecture of Advent. During the first part — from the beginning until 16 December — the liturgy looks above all towards the end of time: the texts speak of the Day of the Lord, of the Son of Man returning, of watchfulness. Only from 17 December does the gaze draw near the crib and fix upon the imminent Nativity^[9]. One season, then, but two focuses: the child of Bethlehem and the King of glory.

The three comings according to St Bernard

Spiritual tradition deepened this duality by adding a third term. In an Advent sermon which the Church still reads today at the Office of Readings, St Bernard of Clairvaux distinguishes three comings of Christ: between his coming in the flesh, at Christmas, and his coming in glory, at the end of time, he places an intermediate coming, hidden and present, by which Christ comes into the soul of each believer.

"He came first in flesh and weakness; then, in the meantime, he comes in spirit and power; finally he will come in glory and majesty. […] This intermediate coming is hidden: only the elect see it within themselves." — St Bernard of Clairvaux, Sermon 5 for Advent^[10]

This doctrine of the adventus medius — the "middle coming" — illuminates the practical meaning of Advent. We prepare not only to celebrate a past anniversary, nor only for a distant future: we welcome now, through grace and the sacraments, Him who comes to dwell in the heart. Advent is therefore not a nostalgic parenthesis, but the season when the first and the last comings meet in a present coming.

A season that opens the liturgical year

There is one last reason for Advent's existence: it is with Advent that the liturgical year begins. The Church does not start her year on the civil 1st of January, nor at Easter, but on the first Sunday of Advent^[11]. The choice is rich in meaning: before retracing the whole mystery of Christ — his birth, his life, his Passover, the sending of the Spirit — the Church puts herself back in the posture of one who waits. She begins each cycle not with a celebration, but with a desire. The Christian year opens upon a hope stretched towards Him who comes: which is to say that the believer's whole life is, at bottom, an advent.

Advent did not fall ready-made from the liturgical sky. Like Lent, it formed slowly, out of diverse practices, before settling into the shape we know. Two currents fed it: a Gallic and Spanish current, penitential, inherited from a forty-day fast; and a Roman current, more festive, turned towards preparing Christmas. Today's Advent is the meeting of the two.

First traces: Gaul and Spain in the 4th century

The oldest traces of an organised preparation before Christmas appear in the West at the end of the 4th century, in Gaul and Spain. In 380, the Council of Saragossa, convened chiefly to condemn the excesses of the Priscillianists, asked the faithful to be assiduous at church from 17 December until Epiphany^[12]. This was not yet an "Advent" in the proper sense — the measure aimed first at controlling practices deemed suspect — but one can already see emerging the idea of a marked season in the weeks preceding the manifestation of the Lord.

This first clue is precious for understanding why Advent exists: it is born of a very concrete pastoral need — gathering the people, preparing them, orienting them towards the great feast of Christ's coming. The form would follow; the intuition was already there.

"St Martin's Lent": Perpetuus of Tours

It is in Gaul, in the 5th century, that the pre-Christmas waiting takes on real substance. Tradition attributes to St Perpetuus, bishop of Tours, the institution of a fast stretching from the feast of St Martin (11 November) until Christmas, at the rate of three days a week^[13]. This weeks-long penance, modelled on the Lent that prepares Easter, was soon popularly called "St Martin's Lent"^[14].

The parallel with Lent is illuminating. For the Gallic sensibility, awaiting Christmas did not go without conversion: one does not receive the coming Saviour without preparing one's heart through penance. Advent owes that austere tinge — violet, fasting, sobriety — to this Gallic origin, not to Rome.

The Council of Mâcon and the Gallic spread

The usage of Tours then spread throughout Frankish Gaul. The Council of Mâcon, at the end of the 6th century, gave it regional scope: its canon prescribed fasting on Mondays, Wednesdays and Fridays from St Martin's day until Christmas, and celebrating those days "as in Lent".

"From St Martin's day until Christmas, fasting is to be observed on Monday, Wednesday and Friday, and on those days the sacrifice is to be celebrated as in Lent." — Council of Mâcon (585), canon 9^[15]

With Mâcon, the Gallic Advent was complete: a season of about forty days, penitential, modelled on Lent, and henceforth imposed by conciliar authority. It is this long, austere form that the Latin West would receive, before combining it with the Roman usage.

The Roman Advent: preparing the feast of Christmas

At Rome, the development was different and later. The City knew no "St Martin's Lent". When an Advent appears there, in the 6th century, it is from the outset turned towards the joyful preparation of Christmas rather than prolonged penance. The oldest Roman liturgical books bear witness to it: the Gelasian sacramentary and the Gregorian sacramentary contain Masses preparing for the Nativity — five in the Gregorian, spread over five weeks^[16]. Tradition readily connects the organisation of this season to St Gregory the Great (pope from 590 to 604), to whom several Advent collects and homilies are attributed^[17].

The Roman Advent thus brings to the Latin Advent its Christological and joyful tone: not first mortification, but welcoming Him who comes. The fusion of the two currents — Gallic penance and Roman joy — would give Advent its own balance: a violet of conversion, but without Lenten mourning; a tempered fast, but real watchfulness; and already, on the third Sunday, a breakthrough of joy.

From five to four weeks: the fixing

One last adjustment remained: the length. The primitive Roman Advent counted five or six weeks according to place and book. It is the reform attributed to Pope St Gregory VII (1073–1085) that brought the Roman Advent back to four weeks, a form that would then prevail over almost the whole Latin West^[18]. The number is anything but arbitrary: four weeks suffice to unfold the twofold expectation without diluting it, and tradition readily saw in it the symbol of the four thousand years — a conventional figure — during which humanity was said to have awaited the Messiah since Adam.

Stages in the formation of Advent

The length of Advent looks simple — four Sundays — but it hides two subtleties: a number of days that varies from year to year, and notable exceptions according to rite. Explaining them answers a concrete question many ask: exactly how long does Advent last?

Why four Sundays in the Roman rite

In the Roman rite, Advent always counts four Sundays, but a variable number of days. The reason is that its end is fixed — the evening of 24 December — while its beginning depends on the weekday on which Christmas falls. Advent begins on the Sunday closest to 30 November (feast of St Andrew), so that the fourth Sunday can fall anywhere between 18 and 24 December. Depending on the year, Advent therefore lasts from twenty-two to twenty-eight days^[19]. The fourth Sunday can even coincide with Christmas Eve, reducing the fourth week to a few hours.

Six weeks in the Ambrosian and Mozarabic rites

The Roman rite is not the only one in the Latin Church. At Milan, the Ambrosian rite — inherited from St Ambrose — has kept an Advent of six weeks, beginning on the Sunday after St Martin's day, faithful in this to the ancient Gallic and Milanese tradition^[20]. The Mozarabic rite, proper to certain churches in Spain, likewise observes a longer Advent. These usages are not anomalies: they are living witnesses of the long, penitential Advent before the Roman reform, preserved where Rome did not unify the liturgy. The four-week Advent is the most widespread form, not the only legitimate one.

The following table compares the length of Advent in the principal Latin rites.

When exactly Advent begins and ends

The official rule is clear, and removes any hesitation about dates:

"Advent begins with First Vespers of the Sunday that falls on or closest to 30 November, and it ends before First Vespers of Christmas." — Universal Norms on the Liturgical Year and the Calendar, no. 40^[21]

Advent therefore ends not on the morning of 25 December, but on the evening of the 24th, at the hour when the celebration of Christmas opens. This precision matters: it shows that Advent and Christmas do not overlap but follow one another — expectation gives way to coming at the very instant the Church begins to sing the Nativity.

Understanding why Advent exists is not enough: we must also see how the Church translates this waiting into her prayer and signs. Every detail of Advent's liturgy — its colour, its chants, its silences — expresses the same thing: watchful expectation of Him who comes.

Two parts: before and after 17 December

Advent is lived in two stages, separated by a clear hinge, 17 December. Until that date, the liturgy is dominated by eschatological expectation: we watch, we hope for the Lord's return, we hear Isaiah announcing a reconciled world. From 17 December until the 24th, the tone changes: the Church prepares directly for the Nativity^[22]. It is the final straight, the week of the "O" antiphons, when expectation grows more pressing and more tender, turned towards the child about to be born.

Violet, no Gloria, Alleluia kept

Advent's colour is violet, the sign of penance and conversion, as in Lent. But Advent is not Lent: its penance is gentler, more joyful, because it awaits a birth, not a Passion. This nuance reads in a precise liturgical detail: during Advent, the Sunday Gloria is omitted — to be kept intact for Christmas night, when the angels will sing it — but the Alleluia is kept, unlike in Lent^[23]. Advent thus holds back its joy without extinguishing it: it stores it up so that it may burst forth at Christmas.

Gaudete Sunday

In the midst of this sobriety, the third Sunday brings a breakthrough of joy. It is called Gaudete Sunday, after the first word of its entrance chant: "Gaudete in Domino semper" — "Rejoice in the Lord always" (Phil 4:4)^[24]. On that day, the celebrant may wear rose vestments, the violet lightening as Christmas approaches. The meaning is clear: the waiting is nearing its end, the Lord is at hand, and joy can no longer be fully contained. The rose of Gaudete is Advent's smile.

The great "O" antiphons and ERO CRAS

The summit of Advent's liturgy lies in the seven great "O" antiphons, sung at the Magnificat of Vespers from 17 to 23 December. Each begins with the exclamation "O" and invokes Christ under an Old Testament title: O Sapientia (Wisdom), O Adonai (Lord), O Radix Jesse (Root of Jesse), O Clavis David (Key of David), O Oriens (Dayspring), O Rex gentium (King of the nations), O Emmanuel (God-with-us)^[25]. These titles sketch the whole portrait of the awaited Messiah, and each antiphon closes with a supplication: "Come!"

These antiphons conceal a famous secret. Take the initial of each one's central title — Sapientia, Adonai, Radix, Clavis, Oriens, Rex, Emmanuel — and read them from the last to the first: they form the two Latin words ERO CRAS: "Tomorrow, I shall be there"^[26]. It is, as it were, Christ's reply to the Church calling upon him for seven evenings: to her who cries "Come!", the Lord answers "Tomorrow, I shall be there" — and the day after the seventh antiphon, on the evening of the 24th, Christmas begins. The great antiphons are the matrix of the famous hymn Veni, veni, Emmanuel^[27].

Three guides: Isaiah, John the Baptist, Mary

Advent's liturgy stages three figures who lead the people towards Christmas. The prophet Isaiah opens almost every reading: he is the voice of Israel's hope, announcing Emmanuel, the shoot of Jesse, the Prince of Peace. John the Baptist dominates the central Sundays: he is the forerunner, the voice crying in the wilderness "Prepare the way of the Lord", calling to conversion. Finally, as Christmas approaches, the Virgin Mary takes centre stage: she is waiting made alive, she who already bears within her the One the world hopes for (see Why is Mary called Mother of God?). These three guides sum up Advent's three attitudes: hoping with Isaiah, being converted with John the Baptist, welcoming with Mary.

Advent did not stay locked inside churches: it gave rise to domestic signs that extend its spirit into families. These familiar objects — the wreath, the calendar — are not mere decorations: they are pedagogies of waiting, concrete ways of counting the days and keeping desire alive.

The Advent wreath

The Advent wreath is today the most widespread sign of this season. Yet its origin is recent and, remarkably, Protestant: it was invented in 1839, at Hamburg, by the Lutheran pastor Johann Hinrich Wichern^[28]. Wichern ran the Rauhes Haus, a home for poor children; to help the children wait patiently until Christmas, he fixed candles on an old cart wheel, lighting one more each day — four large white candles for the Sundays, and small candles for the weekdays^[29].

The symbolism was quickly enriched, and the usage spread through all Western Christendom, Catholics included. The wreath's circle, without beginning or end, evokes God's eternity; the green branches, life persisting in the heart of winter; and above all, the growing light — one more candle each Sunday — figures Christ, the "light of the world", whose approach gradually dispels the darkness. Lighting one more candle is saying in gestures that waiting progresses and light is coming.

The Advent calendar

Born likewise in 19th-century Lutheran Germany, the Advent calendar pursues the same pedagogical aim: opening one "window" a day, from 1 to 24 December, to make tangible the time that brings Christmas nearer. In its earliest form, each window revealed a pious picture or a verse of Scripture. Its commercial, chocolate version has often obscured its meaning: learning the patience of waiting, day after day, and keeping desire awake. Properly understood, the Advent calendar is a tiny catechesis of the "already and not yet".

Rorate caeli: the song of desire

To these domestic signs corresponds, in churches, a chant that sums up all of Advent: the Rorate caeli. Drawn from the prophet Isaiah — "Drop down dew, ye heavens, from above, and let the clouds rain the Just One; let the earth be opened and bring forth the Saviour" (Is 45:8)^[30] — it lifts towards heaven the cry of a world awaiting its Saviour. The Rorate Masses, celebrated at dawn by candlelight alone, picture this waiting: we pray in the half-dark, turned towards a light not yet risen. It is, in a single scene, the whole definition of Advent — watching in the night while awaiting the dawn.

Why does Advent exist? We can now answer in a word: so that the Church may never forget to wait. The permanent risk of faith is to settle down, to take salvation for granted, to celebrate Christmas as a closed memory. Each year, Advent reopens the breach of desire: it recalls that Christ came, that he still comes, and that he will come again.

Watching, hoping, desiring

St Bernard's three comings give Advent its practical depth. Watching, because the Lord will return at an hour we do not expect. Desiring, because the remembrance of Christmas is only worthwhile if it rekindles expectation. And above all welcoming now that hidden, intermediate coming by which Christ, "in spirit and power"^[31], comes to dwell in the heart that opens to him. Advent is not turned towards the past: it is the season of a presence offered, to be received today.

Living the four weeks

Understanding Advent is only worthwhile if it helps us live it. Tradition proposes simple, proven means: more assiduous prayer, in the silence of waiting (see How to pray when distracted?); a sobriety that hollows out desire, inherited from "St Martin's Lent" (see Why fast?); conversion of heart, at John the Baptist's call (see What is repentance?); and charity, which leaves our hands free to welcome Him who comes. Four weeks are none too many to relearn hope. That is exactly the measure the Church gives herself, year after year, to lead her children — from Israel's expectation to the crib, and from the crib to the Day when Christ will return in glory.

• Why is Christmas celebrated on 25 December?
• Why does Lent last forty days?
• Why fast?
• Why is Friday penitential?
• Why does Easter change date?
• Why is Mary called Mother of God?
• How to explain the Incarnation simply?
• What is repentance?