Recapitulation and Christ’s humanity
Recapitulation is a powerful argument against docetism, the belief that Christ only seemed human, because it shows that Christ needed to share our humanity to save us. The Valentinians thought that he only appeared to have human flesh. Irenaeus responded, ‘What he was, that he also appeared to be.’ For a lot of theologians, the virgin birth demonstrates Christ’s deity. Irenaeus used it to prove his humanity: if Christ did not receive human flesh from Mary, why was she involved in his birth at all? If Christ was not human, he could not undo humanity’s errors. If Christ could not suffer, he did not die for us.
Irenaeus used the virgin birth to create another parallel with Adam. To recapitulate Adam, Christ needed to be Adam's descendent, but he also needed a birth like Adam’s. Only a virgin birth could fulfil both criteria. As Jesus’s birth was fatherless, so was Adam formed from ‘virgin’ soil, without male seed. Irenaeus says:
For as by the disobedience of the one man who was originally moulded from virgin soil, the many were made sinners, and forfeited life; so was it necessary that, by the obedience of one man, who was originally born from a virgin, many should be justified and receive salvation.
As the new Adam, Jesus was the first in a new series of humans: those who are reconciled to God and given immortality. The virgin birth is essential to Christ’s ability to recreate humanity.
Images of salvation
Finally, Irenaeus used recapitulation to describe the salvation Jesus won by defeating evil. Recapitulation is the restoration of right headship—in both Greek and Latin, ‘recapitulation’ comes from the word for head. Hence recapitulation means that humans are restored from Satan’s tyranny to Christ, their true head. Using striking imagery, Irenaeus described how Christ descended into humanity’s imprisonment, for a human had to regain what was lost when Satan defeated humanity. Then, gathering us inside himself, he broke that prison open. The gates, as it were, had to be unlocked from inside for the victory to be legitimate. The deliverer also needed to be divine, since Satan’s conqueror had to be stronger than him. Through his obedience, Christ destroyed humanity’s enemy and set us free.
This is not the only salvation metaphor Irenaeus used. Christ replaced humanity’s disobedience with his own obedience; this is the language of substitution. Christ achieved reconciliation with God, propitiation, and the remission of sin. Elsewhere Irenaeus said that humans could only escape mortality if human flesh were united with something incorruptible. But since humans are not naturally immortal, a human had to defeat sin and death, and then share his victory with others. Jesus grants this upgraded, immortal humanity to us through union with himself. The resurrection was proof of Christ’s victory, at the cross and in every battle prior.