“It is important to note that, in accordance with Irenaeus’s general understanding of the human person, the focus of Christ’s work is located in the flesh: it is in the flesh that Christ suffered, and through it that he reconciled the flesh which was in bondage, bringing it into union with God. Nevertheless, the work of redemption is solely the work of God, the incarnate Son, throughout:
‘The Lord has redeemed us through his own blood, giving his soul for our soul, his flesh for our flesh, and has poured out the Spirit of the Father for the union and communion of God and men, bringing God down to men through the Spirit, and lifting man up to God through his incarnation, and by his granting to us incorruptibility, firmly and truly, through communion with him.’ (AH 5.1.1)
Again, it is God, who in man, by himself becoming man, accomplishes the economy.
‘…That the manner of Christ’s incarnation preserved the manner of Adam’s formation is due both to the fact that Adam was a type of Christ and to the need for Christ’s flesh to be that of Adam, if he is to recapitulate all in himself, so becoming the head of all those whose ‘head’ had been Adam.'”
(John Behr, Asceticism and Anthropology in Irenaeus and Clement, p. 62 & 63)