Adam and Christ: The Two Heads of Humanity — Romans 5:12-21

Paul's clearest statement of the two representative heads is Rom 5:12-21: "as one trespass led to condemnation for all, so one act of righteousness leads to justification." Death reigned "from Adam," so that all are bound up with him.

Augustine — On Nature and Grace, reading the Latin in quo omnes peccaverunt as "in whom all sinned"; Council of Trent — Decree on Justification. Irenaeus — Against Heresies — the Eastern accent on restoration. The two heads structure the whole of redemptive history.

The Adam-Christ parallel reaches back to the fall of Gen 3:17-19 and forward to the resurrection harvest of 1Cor 15:22: "as in Adam all die, so in Christ shall all be made alive." Herman Bavinck — Reformed Dogmatics.