On Wednesday of the sixth week of Pascha, we celebrate the Apodosis or Leavetaking of the Feast of Feasts - Holy Pascha. While most Feasts have their Leavetaking on the eighth day, Pascha, the Feast of Feasts, has its Leavetaking on the thirty-ninth day. The fortieth day is the Feast of the Lord's Ascension, which marks the end of the Lord's physical presence on earth. He does not abandon us, however. He has promised to be with us always, even until the end of the age (Matt. 20:28). As we sing in the Kontakion for the Ascension, "Thou didst ascend in glory, O Christ our God, not being parted from those who love Thee, but remaining with them and proclaiming: I am with you and no one will be against you." There is a similar thought expressed in the Apolytikion for the Dormition: "In falling asleep, you did not forsake the world, O Theotokos."
Every major feast has its Apodosis. Why?
The main reason is that the Church once again gives us the opportunity to celebrate the beauty of the feast. When we see or experience something beautiful, it is human nature to desire to have that experience again. For example, when we taste a delicious food, we desire to eat it again. The feasts of Christ and the Theotokos are a sweetness to the soul which arouses the desire to celebrate more than just once.
Such sweetness we experience most of all on the feast of Pascha, which is, as we said, the "Feast of Feasts". for forty days we celebrate the victory of Christ's Resurrection, and the Apodosis ends this celebration on the liturgical level. The festivity of the Resurrection however continues with us throughout the year, especially every Sunday during the Divine Liturgy which is known as a "Small Pascha". But it is not only the Resurrection we celebrate at every Divine Liturgy, but the entire life of Christ and the Theotokos and the Saints.
The services today are celebrated just as on the day of Pascha itself. The daily readings from Holy Scripture, of course, will differ. After the Dismissal at Liturgy, the paschal hymns are no longer sung. The prayer "O Heavenly King" is not said or chanted until Pentecost. The Winding Sheet (Plaschanitsa or Epitaphios) is taken from the altar and is put in its proper place. Even though today is a Wednesday, fish, wine, and oil are permitted.
Troparion
Christ is risen from the dead, trampling down death by death, and to those in the tombs He has given life!
Hypakoe
Before the dawn, Mary and the women came and found the stone rolled away from the tomb. They heard the angelic voice: "Why do you seek among the dead as a man the One who is everlasting life? Behold the clothes in the grave! Go and proclaim to the world: The Lord is Risen! He has slain death, as He is the Son of God, saving the race of men."
Kontakion
Thou didst decend into the tomb, O Immortal One, and Thou didst destory the power of death! In victory didst Thou arise, O Christ God, proclaiming "Rejoice" to the myrrhbearing women, granting peace to Thy apostles, and bestowing resurrection to the fallen.
Paschal Hymn to the Theotokos
The angel cried to Her who is Full of Grace: Rejoice, O Pure Virgin! Again I say: Rejoice! Your Son is Risen from His three days in the tomb! With Himself He has raised all the dead! Rejoice, all you people! Shine! Shine! O New Jerusalem! The Glory of the Lord has shone on you! Exalt now and be glad, O Zion! Be radiant, O Pure Theotokos, in the Resurrection of your Son!
For more on the Paschal and the Pentecostarion period, see the Pentecostarion Resource Page.