“Thus the Son of God, Himself at once the Word of God and Son of man, Mediator of God and men, equal to the Father by the unity of the godhead, and partaker of us through the assumption of the manhood, interceding with the Father for us through that which was man, yet not concealing that as God He was One with the Father, thus speaks: ‘Neither pray I for these alone, but for those also who shall believe through their word on Me; that all may be one, as Thou, Father, art in Me, and I in Thee, that they also may be One in Us, that the world may believe that Thou hast sent Me. And the glory which Thou gavest Me, I have given them, that they may be One as we also are One.’ He said not, that I and they may be One thing, although in that He is the Head of the Church, and the Church His Body, He might say, I and they not One thing, but One person, because the Head and the Body is One Christ. But marking His Godhead as consubstantial with the Father (whence in another place He says, I and the Father are One thing), He wills that His own should be One thing in their own kind, that is, in the consubstantial parity of the same nature, but in Him, because in themselves they could not, as severed from each other by diversity of pleasures, desires, and impurities of sin. From these they are cleansed through the Mediator, so as to be One Thing in Him, not merely by the same nature in which all from mortal men become equal to the angels, but likewise by the same will breathing in perfect harmony together into the same beatitude, welded, as it were, by the fire of charity into One Spirit. For this is the force of His words, That they may be One, as We also are One: that as the Father and the Son are One not only in equality of substance, but also in will, so these also between whom and God the Son is Mediator, may be One Thing not merely by being of the same nature, but also by the same society of affection. And the very point that He is Mediator, by whom we are reconciled to God, He indicates in the words, ‘I in them and Thou in Me, that they may be consummated into One.’ Thus as through the mediator of death we had receded from our Creator, stained and alienated, so through the Mediator of life we might be purified and reconciled, wherein consist our true peace and stable union with Him.” CHAPTER X. THE FIRST AGE OF THE MARTYR CHURCH. “Magnum hæreditatis mysterium! Templum Dei factus est uterus nescientis virum. Non est pollutus ex ea carnem assumens. Omnes gentes venient dicentes, Gloria tibi, Domine.” _Antiphon on Vespers of Circumcision._