leo1Man’s nature has been received by the Son of God into such a union that not only in that Man Who is the first-begotten of all creatures, but also in all His saints there is one and the self-same Christ, and as the Head cannot be separated from the members, so the members cannot be separated from the Head.

[…] It is He whose sufferings are shared not only by the martyrs’ glorious courage, but also in the very act of regeneration by the faith of all the new-born.

For the renunciation of the devil and belief in God, the passing from the old state into newness of life, the casting off of the earthly image, and the putting on of the heavenly form—all this is a sort of dying and rising again, whereby he that is received by Christ and receives Christ is not the same after as he was before he came to the font, for the body of the regenerate becomes the flesh of the Crucified.

This change, dearly-beloved, is the handiwork of the Most High, Who “worketh all things in all” (cf. 1 Cor. 17:6), so that, by the good manner of life observed in each one of the faithful, we know Him to be the Author of all just works, and give thanks to God’s mercy, Who so adorns the whole body of the Church with countless gracious gifts, that through the many rays of the one Light the same brightness is everywhere diffused, and that which is well done by any Christian whatsoever cannot but be part of the glory of Christ.

This is that true Light which justifies and enlightens every man.  This it is that rescues from the power of darkness and transfers us into the Kingdom of the Son of God (Col. 1:13).  This it is that by newness of life exalts the desires of the mind and quenches the lusts of the flesh.

This it is whereby the Lord’s Passover is duly kept “With the unleavened bread of sincerity and truth” by the casting away of “the old leaven of wickedness” (1 Cor. 5:8) and the inebriating and feeding of the new creature with the very Lord.

For naught else is brought about by the partaking of the Body and Blood of Christ than that we pass into that which we then take, and both in spirit and in body carry everywhere Him, in and with Whom we were dead, buried, and rose again, as the Apostle says, “For ye are dead, and your life is hid with Christ in God.  For when Christ, your life, shall appear, then shall ye also appear with Him in glory” (Col. 3:3-4).

Leo the Great (c.400-461): Sermon 63, 3, 6, 7.