The date is always between 19 March and 22 April inclusive. These dates in the Julian calendar, on which Eastern churches in general base their calculations of the date of Easter, correspond throughout the 21st century to 1 April and 5 May in the secularly used Gregorian calendar. The Mass of the Lord's Supper initiates the Easter Triduum, the three days of Good Friday, Holy Saturday and Easter Sunday that commemorate the Passion, Death and Resurrection of Jesus. It is normally celebrated in the evening, when according to Jewish tradition Friday begins.
Use of the names "Maundy Thursday", "Holy Thursday" and the others is not evenly distributed. What is considered the normal name for the day varies according to geographical area and religious allegiance. Thus, while in England "Maundy Thursday" is the normal term, this term is rarely used in Ireland or Scotland in religious contexts. The same person may use one term in a religious context and another in the context of the civil calendar of the country in which he lives.
The Anglican Church uses the name "Maundy Thursday" in the Book of Common Prayer, whereas it treats "Holy Thursday" as an alternative name for Ascension Day. But outside of the official texts of the liturgy, Anglicans sometimes apply the name "Holy Thursday" to the day before Good Friday.
The Roman Catholic Church, even in countries where "Maundy Thursday" is the name in civil legislation, uses the name "Holy Thursday" in its official English-language liturgical books; but, except in these texts, Roman Catholics will sometimes use "Maundy Thursday", especially in England.
In the Eastern Orthodox Church, the name for the holy day is, in the Byzantine Rite, "Great and Holy Thursday" or "Holy Thursday", and in Western Rite Orthodoxy "Maundy Thursday", "Holy Thursday" or both. The Coptic Orthodox Church uses both the terms "Maundy Thursday" and "Covenant Thursday" for the holy day.
In the Maronite Church and the Syriac Orthodox Church, the name is "Thursday of Mysteries".
The Washing of the Feet is a traditional component of the celebration in many Christian Churches, including the Armenian, Ethiopian, Eastern Orthodox, Eastern Catholic, Schwarzenau Brethren/German Baptist groups, Mennonites, and Roman Catholic Churches, and is becoming increasingly popular as a part of the Maundy Thursday liturgy in the Anglican/Episcopal, Lutheran, Methodist, and Presbyterian Churches, as well as in other Protestant denominations. In the Roman Catholic Church, the Mass of the Lord's Supper begins as usual, but the Gloria is accompanied by the ringing of bells, which are then silent until the Easter Vigil. After the homily the washing of feet may be performed. The service concludes with a procession taking the Blessed Sacrament to the place of reposition. The altar is later stripped bare, as are all other altars in the church except the Altar of Repose. In pre-1970 editions, the Roman Missal envisages this being done ceremonially, to the accompaniment of Psalm 21/22, a practice which continues in many Anglican churches.
In the Eastern Orthodox Church, the Lenten character of the services is for the most part set aside, and they follow a format closer to normal. The liturgical colours are changed from the somber Lenten hues to more festive colours (red is common in the Slavic practice). The primary service of this day is Vespers combined with the Liturgy of St. Basil the Great. At this service is read the first Passion Gospel (John 13:31-18:1), known as the "Gospel of the Testament", and many of the normal hymns of the Divine Liturgy are substituted with the following troparion:
Of Thy Mystical Supper, O Son of God, accept me today as a communicant; for I will not speak of Thy Mystery to Thine enemies, neither will I give Thee a kiss like Judas. But like the Thief will I confess Thee: Remember me, O Lord, in Thy Kingdom.In addition to the usual Preparation for Holy Communion, the Orthodox faithful will often receive the Mystery of Unction on Great Wednesday as preparation for the reception of Holy Communion on Great Thursday. It is customary to cover the Altar table with a simple, white linen cloth on this day, as a reminder of the Last Supper. On Great Thursday, the Reserved Sacrament is customarily renewed, a new Lamb (Host) being consecrated for the coming liturgical year, and the remainder from the previous year is consumed. The ceremony of the Washing of Feet will normally be performed in monasteries and cathedrals. Because of the joy of the Institution of the Eucharist, on this day alone during Holy Week wine and oil are permitted at meals. Whenever there is need to consecrate more chrysm it will be done on this day by the heads of the various autocephalous churches. In the evening, after the Liturgy, all of the hangings and vestments are changed to black or some other Lenten colour, to signify the beginning of the Passion.
Beginning on Holy and Great Thursday, the celebration of the Lity (memorial service) is forbidden until Thomas Sunday (the Sunday after Easter).