In antiquity the sons of Israel, on the feast-days or triumphs, offered to God gifts according to the Law, that is sacrifices, whole-burnt offerings, first-fruits and the like.
Therefore St. Gregory [Nazianzen] teaches us also (like them) to make celebration unto the Lord, as they did, and inspires us, saying, “The day of Resurrection,” in place of the “The day of the holy feast, the day of the Divine solemnity, the day of the Pascha of Christ.”
And what does the Pascha of Christ mean? The sons of Israel performed the Pascha, Passover when they departed from Egypt; and now Pascha, the celebration of which St. Gregory is encouraging us to keep, is performed by the soul which departs from the mental Egypt, that is, sin.
For when the soul passes over from sin to virtue, that is when it celebrates the Pascha of the Lord as Evagrius has said; the Pascha of the Lord is the passing over from evil to good.
And thus now today is the Pascha of the Lord, the Day of the Bright Festival, the Day of the Resurrection of Christ Who has crucified sin, Who has died for us and arisen.
Let us also offer to the Lord gifts, sacrifices, whole-burnt offerings–not of irrational animals, which Christ does not wish, for sacrifice and offering hast thou not desired. Whole burnt offerings and oblations for sin hast Thou not demanded (Ps. 39:9, 10). And Isaiah says, of what value to me is the abundance of your sacrifices? saith the Lord (Is. 1:11)….
The Lamb of God was killed for us, according to the words of the Apostle who said For even Christ our Passover is sacrificed for us (I Cor. 5:7).
Christ has redeemed us from the curse of the Law, being made a curse for us – for it is written, cursed is every one that hangeth on a tree (Gal. 3:13, Deut. 21:23) – to redeem them that were under the law, that we might receive the adoption of sons (Gal. 4:5); and so we also should offer Him a certain God-pleasing gift.
And what kind of gift or what kind of sacrifice is it that we should offer to Christ on the day of the Resurrection…? The same Saint [Gregory] instructs us again in this, for having said, “The day of Resurrection” he adds, “Let us offer ourselves.”
Thus also the Apostle says, present your bodies as a living sacrifice, holy, acceptable unto God, which is your reasonable service (Rom. 12:1). And how should we offer our bodies to God as a living and holy sacrifice? By no longer fulfilling the will of our flesh and our thoughts (Eph. 2:3), but acting in the Spirit.
Dorotheos of Gaza (505-565 or 620): Conference 21 – An Explanation of Certain Expressions of St Gregory the Theologian which are Sung together with the Troparia on Holy Pascha @ Pravoslavie.