From the “Second Easter Oration” by St. Gregory Nazianzen (+390) 

To Whom was that Blood offered that was shed for us, and why was It shed? I mean the precious and famous Blood of our God and High priest and Sacrifice. We were detained in bondage by the Evil One, sold under sin, and receiving pleasure in exchange for wickedness. Now, since a ransom belongs only to him who holds in bondage, I ask to whom was this offered, and for what cause? If to the Evil One, fie upon the outrage! If the robber receives ransom, not only from God, but a ransom which consists of God Himself, and has such an illustrious payment for his tyranny, a payment for whose sake it would have been right for him to have left us alone altogether. But if to the Father, I ask first, how? For it was not by Him that we were being oppressed; and next, On what principle did the Blood of His Only begotten Son delight the Father, Who would not receive even Isaac, when he was being offered by his Father, but changed the sacrifice, putting a ram in the place of the human victim? Is it not evident that the Father accepts Him, but neither asked for Him nor demanded Him; but on account of the Incarnation, and because Humanity must be sanctified by the Humanity of God, that He might deliver us Himself, and overcome the tyrant, and draw us to Himself by the mediation of His Son, Who also arranged this to the honour of the Father, Whom it is manifest that He obeys in all things? So much we have said of Christ; the greater part of what we might say shall be reverenced with silence. But that brazen serpent was hung up as a remedy for the biting serpents, not as a type of Him that suffered for us, but as a contrast; and it saved those that looked upon it, not because they believedit to live, but because it was killed, and killed with it the powers that were subject to it, being destroyed as it deserved. And what is the fitting epitaph for it from us? O death, where is your sting? O grave, where is your victory? You are overthrown by the Cross; you are slain by Him who is the Giver of life; you are without breath, dead, without motion, even though you keep the form of a serpent lifted up on high on a pole.

Now we will partake of a Passover which is still typical; though it is plainer than the old one. For that is ever new which is now becoming known. It is ours to learn what is that drinking and that enjoyment, and His to teach and communicate the Word to His disciples. For teaching is food, even to the Giver of food. Come hither then, and let us partake of the Law, but in a Gospel manner, not a literal one; perfectly, not imperfectly; eternally, not temporarily. Let us make our Head, not the earthly Jerusalem, but the heavenly City; not that which is now trodden under foot by armies, but that which is glorified by Angels. Let us sacrifice not young calves, nor lambs that put forth horns and hoofs, in which many parts are destitute of life and feeling; but let us sacrifice to God the sacrifice of praise upon the heavenly Altar, with the heavenly dances; let us hold aside the first veil; let us approach the second, and look into the Holy of Holies. Shall I say that which is a greater thing yet? Let us sacrifice ourselves to God; or rather let us go on sacrificing throughout every day and at every moment. Let us accept anything for the Word’s sake. By sufferings let us imitate His Passion: by our blood let us reverence His Blood: let us gladly mount upon the Cross. Sweet are the nails, though they be very painful. For to suffer with Christ and for Christ is better than a life of ease with others.

Many indeed are the miracles of that time: God crucified; the sun darkened and again rekindled; for it was fitting that the creatures should suffer with their Creator; the veil rent; the Blood and Water shed from His Side; the one as from a man, the other as above man; the rocks rent for the Rock's sake; the dead raised for a pledge of the final Resurrection of all people; the Signs at the Sepulcher and after the Sepulcher, which none can worthily celebrate; and yet none of these equal to the Miracle of my salvation. A few drops of Blood recreate the whole world, and become to all people what rennet is to milk, drawing us together and compressing us into unity.