Each year, the Church enters Lent on Ash Wednesday and comes out of it at Easter, after what she solemnly calls the "holy forty days". The traditional name says it all: the French carême comes from the Latin quadragesima, "the fortieth", and the Greek Church speaks of tessarakoste, built on the number forty[1]. The name of the liturgical season is therefore first of all a number.
But this number hides a puzzle. Whoever takes a calendar and counts the days from Ash Wednesday to Holy Saturday will not find forty: he will find forty-six. And if one stops, as the current liturgy does, at the evening Mass of Holy Thursday, the count is no rounder. Hence the question, simple in appearance and deeper than it looks: why does Lent last forty days — and what exactly does this "forty" mean?
The answer comes in three parts. First, forty is no ordinary figure: throughout the Bible, it is the number of passage, trial and preparation, fixed by Christ's forty days in the desert. Second, the Church did not receive this Lent ready-made: it took shape over the first centuries, from initially very brief paschal fasts, until it settled at forty days in the 4th century. Finally, the way these forty days are counted — subtracting the Sundays, adding Ash Wednesday — explains the apparent gap between the symbolic number and the real calendar.
This article follows this threefold thread. It does not repeat the detail of the rules of fasting and abstinence, treated elsewhere (see Why fast?): it answers precisely the question of the number forty and of the length of Lent.
The number forty in the Bible
Before being a liturgical duration, forty is a biblical number. Scripture uses it so often, and always at the same turning points of salvation, that it has come to signify in itself a spiritual reality: the time of a trial endured, of a generation passing away, of a preparation before a decisive encounter with God.
A number of passage, trial and purification
In biblical symbolism, numbers are not mere quantities: they carry meaning. Forty returns each time a man or a people must pass through a long trial before reaching a new stage. This is not an arithmetical coincidence but a theological constant: God shapes his own in time, and this time willingly takes the measure of forty days or forty years[2]. Lent will inherit this symbolic charge: it will be the time when the Christian, following Christ, crosses the desert to be reborn at Easter.
The great "forties" of the Old Testament
The major episodes of the Old Testament punctuate sacred history to the count of forty. The Flood lasts forty days and forty nights of rain, engulfing a corrupt world and preparing a purified creation (Gen 7:12)[3]. Moses remains forty days and forty nights on Sinai, "eating no bread and drinking no water", before receiving the tables of the Law (Ex 24:18; 34:28; Deut 9:9)[4]. Israel walks forty years in the desert — one year for each of the forty days of exploring the Promised Land — so that the generation of unbelief may die and a people capable of entering the promise may be born (Num 14:33-34)[5]. Elijah, strengthened by a single loaf, walks forty days and forty nights to Horeb, the mountain of God (1 Kings 19:8)[6]. And Nineveh is given forty days to convert before the announced punishment: "Yet forty days, and Nineveh shall be overthrown" (Jon 3:4)[7].
The prophet Ezekiel even lies forty days on his right side "to bear the punishment of the house of Judah, a day for each year" (Ezek 4:6)[8]. Everywhere, the same pattern: forty measures the time of trial, penance or waiting, at the end of which something new begins.
Christ's forty days in the desert
The New Testament gathers and fulfils all this symbolism in a single founding episode. Immediately after his baptism, "Jesus was led up by the Spirit into the wilderness… and he fasted forty days and forty nights, and afterward he was hungry" (Mt 4:1-2; cf. Mk 1:13; Lk 4:1-2)[9]. In this accepted weakness, he confronts and vanquishes the Tempter, opposing each temptation with the Word of God. New Adam, new Moses, new Israel, Christ alone, and without sin, retraces the journey humanity had failed to complete.
It is this fast, and this fast alone, that gives Lent its measure. The Church does not choose forty at random, nor from a taste for round numbers: she models her paschal preparation on her Lord's forty days. The Catechism states it plainly:
"By the solemn forty days of Lent the Church unites herself each year to the mystery of Jesus in the desert." — Catechism of the Catholic Church, § 540[10]
From the Resurrection to the Ascension: forty days again
The symbolism does not stop at the Passion. The Risen Lord extends his visible presence among the Apostles for forty days before ascending into heaven: he presents himself to them "alive after his passion… during forty days, and speaking of the kingdom of God" (Acts 1:3)[11]. The figure thus frames the whole paschal mystery: forty days of fasting in the desert, at the threshold of his public life, forty days of appearances after the resurrection. Lent belongs to this great rhythm: it is the forty days preparing the passage from death to life, as the other forty days crown that accomplished passage.
Why did the Church choose forty days?
The number forty is therefore no late invention: it imposed itself on the Church as soon as she wished to fix a length for her paschal preparation. But between the symbolic intuition and the liturgical institution, a choice, justifications and several centuries were needed. Why, concretely, did the Church retain this measure rather than another?
A Lent modelled on Christ's fast
The first and constant reason is the imitation of Christ. If the Lord fasted forty days before inaugurating his mission, the disciple who wishes to be reborn at Easter walks the same path. Lent is not first of all one ascetic discipline among others: it is a conformation to Christ, a descent with him into the desert to conquer the Tempter with him. All patristic preaching on Lent starts from there. Saint Leo the Great would repeat it every year in Rome: the fast of the forty days is the means by which the Christian "purifies himself" to celebrate the paschal mystery worthily[12].
The spiritual meaning: trial, conversion, paschal preparation
Added to imitation is a spiritual logic. Forty days is long enough for comfort to be disturbed, habits broken, the heart called into question; short enough to remain a journey and not a state. This length makes Lent a true time of conversion, where prayer, fasting and almsgiving combine to prepare the feast (see Why fast? and Why is Friday penitential?). The Catechism ranks Lent among the "times and days of penance in the course of the liturgical year", "intense moments of the Church's penitential practice"[13].
A season that also prepares baptism
Lent was never only a matter of fasting. From antiquity, it was the time of the final preparation of the catechumens who would receive baptism on Easter night. The forty days set the rhythm of the scrutinies, the exorcisms, the handing on of the Creed and the Our Father. This baptismal dimension profoundly shaped the length of Lent: the Church accompanied her future baptized through a forty days of purification, after the pattern of the forty years that had led Israel from slavery to the Promised Land[14]. The liturgy restored after the Second Vatican Council gave full place back to this baptismal character of Lent, without subtracting anything from the number forty.
How did the forty-day Lent take shape?
The Church did not receive a forty-day Lent on the morning of Pentecost. The length we know is the fruit of a long development: in the first two or three centuries, the paschal fast was brief and varied from one Church to another; only in the 4th century did the forty-day Lent impose itself almost everywhere. Tracing this history is the best way to understand why the figure forty finally prevailed.
Before Nicaea: brief and varied paschal fasts
In the 2nd century, there is as yet no Lent in the proper sense. People fast before Easter, but briefly, and very differently according to region. The most precious witness comes from Saint Irenaeus of Lyons, who wrote about 190 to Pope Victor to calm the paschal controversy; his letter, preserved by Eusebius of Caesarea, describes the extraordinary variety of usages:
"For the controversy is not only concerning the day, but also concerning the very manner of the fast. For some think that they should fast one day, others two, yet others more; some moreover count their day as forty hours day and night. And this variety in its observance has not originated in our time, but long before in that of our ancestors." — Saint Irenaeus of Lyons, letter to Pope Victor, quoted by Eusebius of Caesarea, Ecclesiastical History, V, 24[15]
The text is decisive: at the end of the 2nd century, the paschal "fast" could be only one day, two days, or forty hours — symbolizing Christ's time in the tomb —, never yet forty days[16]. Lent as we understand it did not exist. The Apostolic Constitutions, a 4th-century Syrian collection, still witness to a paschal fast centred on Holy Week, distinct from the great forty days then taking shape[17].
The Council of Nicaea (325) and the first mention of the "fortieth"
It is with the first ecumenical council, Nicaea (325), that the word which will become the name of Lent appears for the first time in an official text. Canon 5 prescribes two provincial synods a year, one of them "before the tessarakoste*"* — that is, before the "fortieth", before Lent[18]. The Greek term tessarakoste ("fortieth"), exactly parallel to pentekoste ("fiftieth", Pentecost), henceforth designates a forty-day period before Easter.
Historians debate the precise sense the canon gives the word — a length already fixed everywhere, or a usage still becoming general[19]. But the fact stands: in 325, on the horizon of the bishops gathered under Constantine, tessarakoste is a common landmark of the ecclesial calendar. The forty-day Lent is becoming the usage of the whole Church.
Saint Athanasius and the forty-day Lent at Alexandria
The clearest witness of this generalization comes from Alexandria. Each year, the bishop addressed to his faithful a Festal Letter announcing the date of Easter and the discipline of Lent. In those of Saint Athanasius (written from 329 and in the 330s), Lent appears as a forty-day fast preceding the paschal week, which the bishop strives to impose on all Egypt on the model of what is practised "everywhere in the world"[20]. Athanasius explicitly invokes the forty-day fast of Moses, Elijah and the Lord. At the same time, Jerusalem, Syria, Rome and the West gradually adopt a similar discipline, with different ways of counting.
Saint Leo the Great: a fast "of apostolic institution"
In the 5th century, Lent is established everywhere. In Rome, Saint Leo the Great (pope from 440 to 461) devotes each year a series of sermons to it which remain among the finest texts on the subject. Leo holds the forty-day fast to be an apostolic institution which the faithful must fulfil as a sacred debt[21]. Above all, he recalls insistently its interior meaning:
"Let our fast consist not only in abstinence from food… but far more in renouncing vices." — Saint Leo the Great, Sermon 42 (on Lent)[22]
Historical criticism observes that this "apostolic institution" is a retrospective theological reading: the texts of the first two centuries, as seen above, know nothing of a forty-day fast[23]. But Leo's intuition is right in substance: Lent prolongs the fast of Christ himself, and carries in germ what the Church received from her origins. The length became precise with time; the mystery it expresses is apostolic.
The stages of the formation of Lent
The establishment of the forty-day Lent can be summed up in a few great stages, from the brief fasts of the origins to the stabilized discipline of the Middle Ages.
- c. 190Irenaeus' letter to Victor
Saint Irenaeus of Lyons describes, in a letter preserved by Eusebius, the diversity of paschal fasts: one day, two days, or forty hours. As yet no forty-day Lent.
- 325The Council of Nicaea
Canon 5 mentions for the first time the tessarakoste, the "fortieth" — the first official witness of a forty-day Lent.
- c. 331-339Athanasius' Festal Letters
At Alexandria, Saint Athanasius imposes on all Egypt a forty-day fast before the paschal week, on the model of Moses, Elijah and Christ.
- c. 440-461The sermons of Leo the Great
In Rome, the forty-day Lent is firmly established; Saint Leo holds it to be an apostolic institution and preaches its spiritual meaning.
- c. 600Ash Wednesday
To bring the effective fasting days to forty (Sundays not being fasted), four days are added before the first Sunday of Lent, in the wake of Saint Gregory. Lent now begins on a Wednesday, the caput ieiunii.
But how are the forty days counted?
There remains the opening puzzle: why, counting on a calendar, does one not find forty days between Ash Wednesday and Holy Saturday? The answer lies in an ancient rule and a medieval adjustment. Understanding the reckoning of Lent resolves the apparent paradox of the number forty.
Why there is no fasting on Sunday
The key to the count is a rule as old as the Church: one never fasts on Sunday. Each Sunday is a little Easter, a weekly memorial of the Resurrection; fasting, which is mourning and penance, would be out of place there. This rule is so firm that it runs through the whole Latin tradition: even in the heart of Lent, the six Sundays remain days of joy, exempt from fasting[24]. Hence a "forty-day" period of fasting cannot coincide with forty calendar days: the duration must be stretched so that, Sundays subtracted, a full forty fasted days remain.
The thirty-six days: the "tithe of the year"
For centuries, the Roman Lent counted six weeks, from the first Sunday of Lent to Holy Saturday. Six weeks make forty-two days; take away the six Sundays, which are not fasted, and thirty-six fasting days remain. The Fathers loved this number thirty-six, in which they saw the tithe of the year: thirty-six days offered to God out of the three hundred and sixty-five of the year, about one tenth. Saint John Cassian develops it at length:
"The tithe of the sum of all the days contained in the course of the year is thirty-six and a half days… We are commanded to offer tithes of our goods; how much more must we offer the tithes of our very life." — Saint John Cassian, Conferences, XXI, 25[25]
Saint Gregory the Great takes up exactly this reckoning in a homily preached on the first Sunday of Lent:
"From this day to the joys of the paschal solemnity, there are six weeks, that is forty-two days; but as the six Sundays are subtracted from them, no more than thirty-six fasting days remain… we mortify our body for thirty-six days, as the tithe of the year." — Saint Gregory the Great, Homilies on the Gospels, homily 16, ch. 5[26]
Saint Gregory the Great and the addition of Ash Wednesday
Gregory's text reveals a decisive fact: around the year 600, the Roman Lent still began on the first Sunday and counted only thirty-six fasting days, not forty. To make the real length of the fast coincide with the symbolic number of Christ's forty days, four days were added before that first Sunday: Wednesday and the three days following. Lent then began to start on a Wednesday — the caput ieiunii, the "head of the fast", which would become Ash Wednesday[27].
Liturgical tradition readily attributes this addition to Saint Gregory the Great himself. Historians are more cautious: Gregory's homily attests precisely that in his time the count was still thirty-six days, suggesting the addition of the four days spread in his wake rather than by a dated personal decree[28]. Whatever the detail, the result is clear and lasting: from the early Middle Ages, the Roman Lent comprises forty effective fasting days, opened by Ash Wednesday.
The classic reckoning: forty-six days minus six Sundays
The opening paradox can now be resolved. From Ash Wednesday to Holy Saturday, the calendar counts forty-six days. These forty-six days contain six Sundays, which are not fasted. Forty-six minus six makes forty: exactly the forty fasting days of Lent. The symbolic number and the real calendar are reconciled by this simple subtraction.
| From Ash Wednesday to Holy Saturday | Days |
|---|---|
| Calendar days (Ashes → Holy Saturday) | 46 |
| Minus the six Sundays (never fasted) | − 6 |
| Effective fasting days | 40 |
That is why one often hears that "Sundays do not count in Lent". The formula is correct for the fast — a Sunday is never a fasting day —, but it needs nuance: Sundays fully belong to the liturgical season of Lent, whose march toward Easter they punctuate. They are not excluded from it; they are its joyful halts.
The current liturgical definition
The liturgical reform following Vatican II slightly shifted the bounds of Lent, without touching the number forty. Since 1969, the Universal Norms for the Liturgical Year fix its length thus:
"The season of Lent runs from Ash Wednesday until the Mass of the Lord's Supper exclusive." — Universal Norms for the Liturgical Year and the Calendar (1969), no. 28[29]
Lent therefore now ends on Holy Thursday evening, at the entrance of the Easter Triduum (Supper, Passion, Vigil), which forms a liturgical season apart. The exact count of days from Ash Wednesday to Holy Thursday no longer falls rigorously on forty: the reform favoured the coherence of the Triduum over arithmetic. But the name Quadragesima, the "forty days", remains: it expresses less a precise count than the symbolic measure inherited from Christ in the desert[30].
Eastern Lent: forty days counted otherwise
The Eastern Churches have also kept a "Great Forty Days" — Tessarakoste — of forty days, but they count it in quite another way. The comparison illuminates, by contrast, the logic of the Latin Lent.
The Byzantine Great Forty Days
In the Byzantine rite, the Great Lent is a block of forty full days, distinct from Holy Week. It begins on Clean Monday (the Monday after Forgiveness Sunday) and ends on the Friday before Lazarus Saturday[31]. Where the West subtracts Sundays from the fasting count, the East includes Sundays in the forty days of the Forty, but takes Holy Week entirely out, held as a sacred season apart. One obtains thus, on either side, a "forty days" — but built on two opposite reckonings.
Two ways of holding to the number forty
The following table sums up these two logics. It shows that the figure forty is, in both traditions, the untouchable landmark: it is the bounds and the place of Holy Week that differ.
| Latin Lent (Roman rite) | Byzantine Great Lent | |
|---|---|---|
| Name | Quadragesima / Lent | Tessarakoste / Great Forty Days |
| Beginning | Ash Wednesday | Clean Monday |
| End | Mass of the Supper (Holy Thursday evening) | Friday before Lazarus Saturday |
| Sundays | Subtracted from the fasting count | Included in the forty days |
| Holy Week | The Easter Triduum is apart | Holy Week entirely apart |
| Logic of the "forty" | 46 days − 6 Sundays = 40 fasted | 40 full days, excluding Holy Week |
This divergence is no contradiction: it says that the number forty imposed itself on all Christendom as the right measure of paschal preparation, each tradition then adjusting it to its own liturgical calendar.
What remains of the number forty today?
At the end of this inquiry, the "forty" of Lent no longer appears as an approximate label, but as a number laden with the whole Bible and shaped by fifteen centuries of usage. Three ways of counting — thirty-six days as "tithe of the year", forty fasting days through the addition of Ash Wednesday, forty full days in the East — converge toward one same symbol.
A symbol deeper than a count
The essential thing is therefore not arithmetical exactness, but the meaning the number carries. Forty is the time needed to cross a desert, let the old man die and prepare an Easter. Whether the calendar falls on forty, forty-two or forty-six days according to the way of counting, Lent remains that spiritual forty days in which the Christian follows Christ into the desert to rise with him. The number is less a duration than a figure: that of a required passage from death to life.
Living the forty days
Understanding why Lent lasts forty days is worthless unless it helps to live them. Tradition proposes for this the three classic works of penance — prayer, fasting, almsgiving (see Why fast?) —, sustained by Friday penance (see Why is Friday penitential?), and ordered to conversion of heart and reconciliation with God (see What is repentance? and How to make a good confession?). Forty days are not too many for this. It is, exactly, the measure Christ gave himself — and offers his Church, year after year, to lead her to Easter.
To go further
Notes and References
The French carême comes from popular Latin quaresima, a contraction of quadragesima ("fortieth [day]"), elliptical for quadragesima dies ante Pascha. The Greek tessarakoste ("fortieth") is formed exactly like pentekoste ("fiftieth", Pentecost). See the article "Lent", Catholic Encyclopedia, vol. 9, Robert Appleton Company, New York, 1910. (The English word Lent comes from Old English lencten, "spring season"; the Romance languages kept the Latin quadragesima.)
1Catechism of the Catholic Church, § 540: "By the solemn forty days of Lent the Church unites herself each year to the mystery of Jesus in the desert." § 540 explicitly links Lent to Christ's forty days tempted in the desert (Mt 4:1-11).
2 10 14Book of Genesis, 7:12: "The rain fell upon the earth forty days and forty nights." Cf. Gen 7:4 and 7:17.
3Book of Exodus, 24:18 and 34:28; Deuteronomy, 9:9, 18. Moses remains forty days and forty nights on Sinai, eating and drinking nothing, before receiving the tables of the Law.
4Book of Numbers, 14:33-34: "According to the number of the days in which you spied out the land, forty days, for every day a year, you shall bear your iniquity." The forty years in the desert mirror the forty days of exploring the Promised Land.
5First Book of Kings, 19:8: Elijah, strengthened by the angel's bread, walks forty days and forty nights to Horeb, the mountain of God.
6Book of Jonah, 3:4: "Yet forty days, and Nineveh shall be overthrown." The Masoretic Hebrew text and the Vulgate read forty days (the Septuagint reads three); the Latin tradition retains forty.
7Book of Ezekiel, 4:6: the prophet lies forty days on his right side, "a day for a year", to bear symbolically the punishment of the house of Judah.
8Gospel according to Saint Matthew, 4:1-2; parallels Mark 1:12-13 and Luke 4:1-2. Christ's forty-day fast in the desert, followed by the three temptations, opens his public life and serves as the direct model of Lent.
9Acts of the Apostles, 1:3: the Risen Lord presents himself alive to the Apostles "during forty days", speaking of the kingdom of God, before the Ascension. The number forty thus frames the whole paschal mystery.
11Saint Leo the Great, Sermon 42 (4th on Lent), II, Sources Chrétiennes no. 49 bis, Éditions du Cerf; Patrologia Latina vol. 54, col. 275-280. Leo insists: the true fast is not first of all abstinence from food, but renouncing vices and practising charity.
12 22Catechism of the Catholic Church, § 1438: "The seasons and days of penance in the course of the liturgical year (Lent, and each Friday in memory of the death of the Lord) are intense moments of the Church's penitential practice."
13Saint Irenaeus of Lyons, letter to Pope Victor (c. 190), quoted by Eusebius of Caesarea, Ecclesiastical History, book V, ch. 24, § 12-13. Reference edition: Sources Chrétiennes no. 41, Éditions du Cerf. Irenaeus attests the diversity of paschal fasts before Easter in the first two centuries.
15The reading "forty hours" (not forty days) is the Greek text established by modern criticism; a late Latin translation by Rufinus punctuated differently so as to read "forty days", a reading rejected today. See the apparatus of the Sources Chrétiennes no. 41 edition and the article "Lent", Catholic Encyclopedia, vol. 9, 1910. The "forty hours" refer to Christ's time in the tomb, not to a Lent.
16Apostolic Constitutions, book V, ch. 13-18 (Syrian compilation, c. 380), Sources Chrétiennes no. 329, Éditions du Cerf. The text distinguishes a fast of the forty days and a fast proper to Passion week, witnessing to a discipline still being fixed in the 4th century.
17First Council of Nicaea (325), canon 5. Greek text: the meeting of provincial synods must take place "before the tessarakoste" (πρὸ τῆς τεσσαρακοστῆς). Reference edition: G. Alberigo (ed.), Decrees of the Ecumenical Councils, vol. I, Sheed & Ward / Georgetown, 1990, p. 8; cf. the French edition Les Conciles œcuméniques. Les Décrets, vol. II-1, Éditions du Cerf, 1994. This is the first official mention of the tessarakoste.
18Historians discuss the exact sense of tessarakoste in 325: a forty-day period already fixed everywhere, or a usage still becoming general. See the article "Lent", Catholic Encyclopedia, vol. 9, 1910, which calls the precise sense of the canon "debatable".
19Saint Athanasius of Alexandria, Festal Letters (from 329, especially those of the 330s), critical ed. L.-T. Lefort, CSCO, Louvain, 1955. Athanasius strives to impose on all Egypt the forty-day fast preceding the paschal week, on the model of Moses, Elijah and Christ, invoking the usage of the universal Church.
20Saint Leo the Great, sermons on Lent (De Quadragesima), c. 440-461, Sources Chrétiennes no. 49 bis, Éditions du Cerf. Leo presents the forty-day fast as an "apostolic institution" to be fulfilled with fervour.
21Attributing an "apostolic institution" to the forty-day Lent is a retrospective theological interpretation: the sources of the first two centuries (Irenaeus, Apostolic Constitutions) know no such fast. The forty-day length was fixed in the 4th century. See the article "Lent", Catholic Encyclopedia, vol. 9, 1910.
23The principle that "one never fasts on Sunday", the day of the Resurrection, is constant in the Latin tradition: each Sunday is a "little Easter" incompatible with the mourning of fasting. Cf. Catechism of the Catholic Church, § 1166-1167 on Sunday, the "day of the Resurrection" and the "first of all feast days".
24Saint John Cassian, Conferences, XXI, 25 (Conference of Abbot Theonas), Sources Chrétiennes no. 64, Éditions du Cerf. Cassian sets out the "tithe of the year": the thirty-six and a half days of the quadragesimal fast represent about one tenth of the three hundred and sixty-five days of the year, offered to God.
25Saint Gregory the Great, Homilies on the Gospels, homily 16, ch. 5 (homily for the first Sunday of Lent), Patrologia Latina vol. 76, col. 1137; transl. Sources Chrétiennes no. 485, Éditions du Cerf. Gregory counts six weeks (forty-two days), minus six Sundays, that is thirty-six fasting days, the "tithe of the year".
26Ash Wednesday, formerly named caput ieiunii ("head / beginning of the fast"), results from adding four days (Wednesday, Thursday, Friday, Saturday) before the old first Sunday of Lent, so as to bring the effective fasting days to forty. The rite of the imposition of ashes is attested in the Gregorian sacramentary and generalized in the 11th century (synod of Benevento, 1091).
27Tradition attributes the addition of the four days and the institution of Ash Wednesday to Saint Gregory the Great (c. 600), but his homily 16 attests that in his time the Roman Lent still counted thirty-six fasting days from the first Sunday. Historians therefore judge that the addition spread in his wake rather than by a dated personal decree. Cf. the article "Lent", Catholic Encyclopedia, vol. 9, 1910.
28Universal Norms for the Liturgical Year and the Calendar (Normae universales de anno liturgico et de calendario), promulgated by Paul VI on 14 February 1969 (motu proprio Mysterii paschalis), no. 28: "The season of Lent runs from Ash Wednesday until the Mass of the Lord's Supper exclusive." Text in the Roman Missal and on vatican.va.
29The Latin name of the liturgical season remains Quadragesima ("forty days") in the Roman Missal, even though the count from Ash Wednesday to the Supper no longer falls exactly on forty days: the word expresses the symbolic measure inherited from Christ's forty days, not a rigorous computation.
30Lenten Triodion (Triodion), liturgical book of the Byzantine rite. The Great Lent (Tessarakoste) runs from Clean Monday (the day after Forgiveness Sunday) to the Friday before Lazarus Saturday; Great Week (Holy Week) constitutes a distinct liturgical season. Cf. The Lenten Triodion, transl. Mother Mary and K. Ware, Faber & Faber, 1978, introduction.
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