Holy Week is the week which precedes the great festival of the Resurrection on Easter Sunday, and which consequently is used to commemorate the Passion of Christ, and the event which immediately led up to it. In Latin is it called hebdomada major, or, less commonly, hebdomada sancta, styling it he hagia kai megale ebdomas. Similarly, in most modern languages (except for the German word Charwoche, which seems to mean "the week of lamentation") the interval between Palm Sunday and Easter Day is known par excellence as Holy Week.
From an attentive study of the Gospels, and particularly that of St. John, it might easily be inferred that already in Apostolic times a certain emphasis was laid upon the memory of the last week of Jesus Christ's mortal life. The supper at Bethania must have taken place on the Saturday, "six days before the pasch" (John 12:1-2), and the triumphant entry into Jerusalem was made from there next morning. Of Christ's words and deeds between this and His Crucifixion we have a relatively full record. But whether this feeling of the sanctity belonging to these days was primitive or not, it in any case existed in Jerusalem at the close of the fourth century, for the Pilgrimage of Ætheria contains a detailed account of the whole week, beginning with the service in the "Lazarium" at Bethania on the Saturday, in the course of which was read the narrative of the anointing of Christ's feet. Moreover, on the next day, which, as Ætheria says, "began the week of the Pasch, which they call here the "Great Week", a special reminder was addressed to the people by the archdeacon in these terms: "Throughout the whole week, beginning from to-morrow, let us all assemble in the Martyrium, that is the great church, at the ninth hour." The commemoration of Christ's triumphal entry into the city took place the same afternoon. Great crowds, including even children too young to walk, assembled on the Mount of Olives and after suitable hymns, and antiphons, and readings, they returned in procession to Jerusalem, escorting the bishop, and bearing palms and branches of olives before him. Special services in addition to the usual daily Office are also mentioned on each of the following days. On the Thursday the Liturgy was celebrated in the late afternoon, and all Communicated, after which the people went to the Mount of Olives to commemorate with appropriate readings and hymns the agony of Christ in the garden and His arrest, only returning to the city as day began to dawn on the Friday. On the Friday again there were many services, and in particular before midday there took place the veneration of the great relic of the True Cross, as also of the title which had been fastened to it; while for three hours after midday another crowded service was held in commemoration of the Passion of Christ, at which, Ætheria tells us, the sobs and lamentations of the people exceeded all description. Exhausted as they must have been, a vigil was again maintained by the younger and stronger of the clergy and by some of the laity. On the Saturday, besides the usual offices during the day, there took place the great paschal vigil in the evening, with the baptism of children and catechumens. But this, as Ætheria implies, was already familiar to her in the West. The account just summarized belongs probably to the year 388, and it is of the highest value as coming from a pilgrim and an eyewitness who had evidently followed the services with close attention. Still the observance of Holy Week as a specially sacred commemoration must be considerably older. In the first of his festal letters, written in 329, St. Athanasius of Alexandria speaks of the severe fast maintained during "those six holy and great days [preceding Easter Sunday] which are the symbol of the creation of the world". He refers, seemingly, to some ancient symbolism which strangely reappears in the Anglo-Saxon martyrologium of King Alfred's time. Further he writes, in 331: "We begin the holy week of the great pasch on the tenth of Pharmuthi in which we should observe more prolonged prayers and fastings and watchings, that we may be enabled to anoint our lintels with the precious blood and so escape the destroyer." From these and other references, e.g., in St. Chrysostom, the Apostolic Constitutions, and other sources, including a somewhat doubtfully authentic edict of Constantine proclaiming that the public business should be suspended in Holy Week, it seems probable that throughout the Christian world some sort of observance of these six days by fasting and prayer had been adopted almost everywhere by Christians before the end of the fourth century. Indeed it is quite possible that the fast of special severity is considerably older, for Dionysius of Alexandria (c. A.D. 260) speaks of some who went without food for the whole six days (see further under LENT). The week was also known as the week of the dry fast (xerophagia), while some of its observances were very possibly influenced by an erroneous etymology of the word Pasch, which was current among the Greeks. Pasch really comes from a Hebrew meaning "passage" (of the destroying angel), but the Greeks took it to be identical with paschein, to suffer.
We may now touch upon some of the liturgical features which are distinctive of Holy Week at the present time. Palm Sunday comes first in order, and although no memory now remains in our Roman Missal of the supper at Bethany and the visit to the "Lazarium", we find from certain early Gallican books that the preceding day was once known as "Lazarus Saturday", while Palm Sunday itself is still sometimes called by the Greeks kyriake tou Lazarou (the Sunday of Lazarus). The central feature of the service proper to this day, as it was in the time of Ætheria, is the procession of palms. Perhaps the earliest clear evidence of this procession in the West is to be found in the Spanish "Liber Ordinum" (see Férotin, "Monumenta Liturgica", V, 179), but traces of such a celebration are to be met with in Aldhelm and Bede as well as in the Bobbio Missal and the Gregorian Sacramentary. All the older rituals seem to suppose that the palms are blessed in a place apart (e.g. some eminence or some other church of the town) and are then borne in procession to the principal church, where an entry is made with a certain amount of ceremony, after which a solemn Mass is celebrated. It seems highly probable, as Canon Callewaert has pointed out (Collationes Brugenses, 1907, 200-212), that this ceremonial embodies a still living memory of the practice described by Ætheria at Jerusalem. By degrees, however, in the Middle Ages a custom came in of making a station, not at any great distance, but at the churchyard cross, which was often decorated with box or evergreens (crux buxata), and from here the procession advanced to the church. Many details varying with the locality marked the ceremonial of this procession. An almost constant feature was, however, the singing of the "Gloria laus", a hymn probably composed for some such occasion by Theodulphus of Orléans (c. A.D. 810). Less uniformly prevalent was the practice of carrying the Blessed Sacrament in a portable shrine. The earliest mention of this usage seems to be in the customs compiled by Archbishop Lanfranc for the monks of Christ Church, Canterbury. In Germany, and elsewhere on the Continent, the manner of the entry of Christ was sometimes depicted by dragging along a wooden figure of an ass on wheels (the Palmesel), and in other places the celebrant himself rode upon an ass. In England and in many parts of France the veneration paid to the churchyard cross or to the rood cross in the sanctuary by genuflections and prostrations became almost a central feature in the service. Another custom, that of scattering flowers or sprays of willow and yew before the procession, as it advanced through the churchyard, seems to have been misinterpreted in course of time as a simple act of respect to the dead. Under the impression the practice of "flowering the graves" on Palm Sunday is maintained even to this day in many country districts of England and Wales. With regard to the form of the blessing of the palms, we have in the modern Roman Missal, as well as in most of the older books, what looks like the complete Proper of a Mass — Introit, Collects, Gradual, Preface, and other prayers. It is perhaps not unnatural to conjecture that this may represent the skeleton of a consecration Mass formerly said at the station from which the procession started. This view, however, has not much positive evidence to support it and has been contested (see Callewaert, loc. cit.). It is probable that originally the palms were only blessed with a view to the procession, but the later form of benediction seems distinctly to suppose that the palms will be preserved as sacramentals and carried about. The only other noteworthy feature of the present Palm Sunday service is the reading of the Gospel of the Passion. As on Good Friday, and on the Tuesday and the Wednesday of Holy Week, the Passion, when solemn Mass is offered, is sung by three deacons who impersonate respectively the Evangelist (Chronista), Jesus Christ, and the other speakers (Synagoga). This division of the Passion among three characters is very ancient, and it is often indicated by rubrical letters in early manuscripts of the Gospel. One such manuscript at Durham, which supposes only two readers, can hardly be of later date than the eighth century. In earlier times Palm Sunday was also marked by other observances, notably by one of the most important of the scrutinies for catechumens and by a certain relaxation of penance, on which ground it was sometimes called Dominica Indulgentiae.