ἐξ αὐτοῦ δὲ ὑμεῖς ἐστε ἐν Χριστῷ Ἰησοῦ, ὃς ἐγενήθη σοφία ἡμῖν ἀπὸ θεοῦ, δικαιοσύνη τε καὶ ἁγιασμὸς καὶ ἀπολύτρωσις, (1st Corinthians 1:30)
For a reference to the below statement -
Thus it is worth nothing right away, especially in view of what follows, that the term which the New Testament uses for redemption, apolutrosis, is derived not from the verb but from the noun lutron which refers not so much to the act as to the cost of redemption. That should warn us that any account of redemption in the New Testament and early church which does not give central significance to the lutron, the price of redemption, is hardly likely to do justice to their understanding. (p26)
So then, perhaps the cost cannot be a mere man… or perhaps, the life given was the cost?