Easter is the feast of the Resurrection of Jesus Christ from the dead — the oldest, highest, and most central celebration of the Christian year. Every other movable feast and fast is calculated from it; every Sunday is a weekly Easter. The date is determined by the Paschal computation established at the Council of Nicaea (325): Easter falls on the first Sunday after the first full moon on or after the vernal equinox (March 21), placing it between March 22 and April 25. The earliest Christians appear to have observed an annual Pascha from a very early period, though the precise origins are debated. The Quartodeciman controversy of the second century — whether to celebrate the Pascha on Nisan 14 (regardless of the day of the week) or always on a Sunday — attests that the observance was already widespread and deeply important by the mid-100s. Polycarp of Smyrna reportedly discussed the matter with Anicetus of Rome around 155 (Eusebius, HE 5.24), and the issue was sharp enough to prompt Victor of Rome to threaten excommunication of the Asian churches, a threat moderated by Irenaeus's famous appeal for peace. The Nicene resolution in favor of the Sunday observance became universal in the mainstream Church, though some groups maintained the Quartodeciman practice for centuries. The Great Vigil of Easter is among the most ancient liturgies in Christianity, with roots traceable to at least the third century (Apostolic Tradition). By the fourth century, Egeria describes an elaborate Jerusalem vigil with baptisms, and Augustine attests a similar pattern in North Africa.

The Great Vigil, which the BCP 2019 describes as 'the first liturgy of Easter Day,' begins in darkness. The Paschal Candle is lit from new fire — a symbol of Christ as the light of the world entering the darkness of the tomb. The Exsultet, the great hymn of praise to the Paschal Candle, is among the most magnificent pieces of Christian hymnody, attested from at least the fourth century (Ambrose may have composed an early version). The vigil readings trace salvation history from creation through the Exodus to the prophets, building to the proclamation of the Resurrection Gospel. Historically, the Vigil was the primary occasion for baptism — new Christians dying and rising with Christ through the waters, emerging to receive their first Eucharist on the night of the Resurrection. The BCP 2019 provides for baptism or renewal of baptismal vows at the Vigil. The Easter morning liturgy opens with the Paschal greeting: 'Alleluia! Christ is risen! / The Lord is risen indeed! Alleluia!' — a form attested across virtually every Christian tradition. The fifty days of Eastertide that follow (through Pentecost) are treated as a single unbroken feast — no fasting, no kneeling for prayer, Alleluias throughout. Easter eggs, the custom of which is documented from at least the thirteenth century, symbolize the sealed tomb and new life breaking forth. Easter is not a day but a season.

The identification of the evangelist with John Mark of Acts (12:12, 25; 13:5, 13; 15:37–39) and with the Mark of Paul's letters (Colossians 4:10, Philemon 24, 2 Timothy 4:11) is traditional but widely accepted. John Mark's mother, Mary, owned the house in Jerusalem where the early Christians assembled (Acts 12:12)—possibly the location of the Last Supper and Pentecost.

Mark accompanied Barnabas and Paul on the first missionary journey but 'left them and returned to Jerusalem' (Acts 13:13)—a departure that Paul regarded as desertion, leading to a sharp disagreement between Paul and Barnabas recorded in Acts 15:37–39. Barnabas took Mark with him to Cyprus; Paul chose Silas instead. The breach was eventually healed—Paul later mentions Mark warmly (Colossians 4:10: 'Marcus, the cousin of Barnabas'; 2 Timothy 4:11: 'Get Mark and bring him with you, for he is very useful to me').

The tradition connecting Mark to Peter is early and strong. Papias of Hierapolis (c. 130), quoted by Eusebius, calls Mark 'Peter's interpreter' (hermēneutēs) who 'wrote down accurately, though not in order, all that he remembered of what the Lord had said or done.' Irenaeus confirms that Mark wrote down Peter's preaching after Peter's death in Rome, and Clement of Alexandria elaborates that the Gospel was composed while Peter was alive but that Peter approved it. This testimony places the composition of the Gospel in the late 60s AD, probably in Rome, shortly before or after Peter's martyrdom under Nero (c. 64–67).

The Gospel itself bears the marks of this origin. It is fast-paced (the word 'immediately,' euthys, appears over forty times), vivid in sensory detail (the green grass at the feeding of the five thousand; the cushion on which Jesus slept in the boat; the Aramaic cries preserved untranslated: 'Talitha koum,' 'Abba,' 'Eloi Eloi lema sabachthani'), and unflinchingly honest about the disciples' failures. Its ending (Mark 16:8) is abrupt and troubling: the women at the tomb, having been told of the resurrection, flee in fear and 'said nothing to anyone, for they were afraid.' Whether this was Mark's intended ending or the original ending was lost and replaced with later supplements (16:9–20) is one of the great puzzles of New Testament textual and literary criticism.

Traditionally, Mark was the evangelist of Egypt, specifically Alexandria, where he founded the Christian community and served as its first bishop. According to late traditions, Mark was martyred in Alexandria by being dragged through the streets with a rope around his neck. His relics were later stolen from Alexandria by Venetian merchants in 828 and brought to Venice, where the Basilica di San Marco was built to house them—making the winged lion (Mark's Evangelist symbol) the emblem of the Venetian Republic and the symbol of the Venetian state to this day.

A persistent tradition identifies the 'young man' who fled naked from Gethsemane (Mark 14:51–52)—a detail found only in Mark's Gospel—as Mark himself. This identification is unprovable but has a certain narrative and autobiographical logic.