Gregory of Nyssa

By the distinction implied in the word mediator he reveals to us the whole aim of the mystery of godliness. Now the aim is this. Humanity once revolted through the malice of the enemy, and, brought into bondage to sin, was also alienated from the true Life. After this the Lord of the creature calls back to him his own creature and becomes Man while still remaining God, being both God and man in the entirety of the two separate natures. Thus humanity was indissolubly united to God, the man that is in Christ conducting the work of mediation, to whom, by the firstfruits assumed for us, all the lump is potentially united.