Adam, the first man, corresponds in some degree to the man who was to come. But the gift of God through Christ is a very different matter from the ‘account rendered’ through the sin of Adam. For while as a result of one man’s sin (Adam’s sin), death by natural consequence became the common lot of every man, it was by the generosity of God, the free giving of the grace of the one man Jesus Christ, that the love of God overflowed for the benefit of all men —Romans 5:15
What a contrast between Adam and Christ!—and what a difference between one man’s sin and God’s forgiveness!
Nor is the effect of God’s gift the same as the effect of that one man’s sin. For in the one case, sin brought its inevitable judgment, and the result was condemnation. But, in the other, countless men’s sins are met with the free gift of grace, and the result is justification before God —Romans 5:16
Think about it. This one man, Adam, brought death to many through his sin, but this one man, Jesus Christ, brought forgiveness to many through God’s mercy.
For if one man’s offense meant that men should be slaves to death all their lives, it is a far greater thing that through another man, Jesus Christ, men by their acceptance of his more than sufficient grace and righteousness should live all their lives like kings! —Romans 5:17
We see, then, that as one act of sin exposed the whole race of men to God’s judgment and condemnation, so one act of perfect righteousness presents all men freely acquitted in the sight of God. (5:18)
Ooh yeah! Adam’s sin brought punishment to all; but Christ’s righteousness makes men right with God, so they can live. Adam caused many to be sinners because he disobeyed God, and Christ caused many to be made acceptable to God because he obeyed.
If interested, you can download the entire study of The Letter to Christians at Rome