For in no other way could we have learned the things of God, unless our Master, existing as the Word, had become man. For no other being had the power of revealing to us the things of the Father, except his own proper Word. What other person “knew the mind of the Lord,” or who else “has become his counselor” (Rom. 11:34)? Again, we could have learned in no other way than by seeing our Teacher and hearing his voice with our own ears, that, having become imitators of his works as well as doers of his words, we may have communion with him, receiving increase from the perfect one … who, redeeming us by his own blood in a manner consonant to reason, gave himself as a redemption for those who had been led into captivity … and redeemed them as his own property … giving his soul for our souls, and his flesh for our flesh. [Our Lord] has also poured out the spirit of the Father for the union and communion of God and man, imparting indeed God to men by means of the Spirit, and, on the other hand, attaching man to God by his own incarnation, and bestowing upon us at his coming immortality, durably and truly, by means of communion with God.
* This excerpt is from “Against the Heresies” by St. Irenaeus of Lyons