Paul presents Jesus Christ as both the last Adam, succeeding where the first Adam failed, and the second man, standing at the head of a new humanity.

The contrast between the first and second Adam
Ro 5:14 By his sin Adam brought universal misery on humanity. In this he is the foreshadower and prototype of Jesus Christ, who through his righteous act brings the universal hope of redemption.

The contrast in nature of the first Adam and the second Adam
Adam was a living being; Jesus Christ is a life-giving being 1Co 15:45

Adam was natural, Jesus Christ is spiritual 1Co 15:46

Adam was earthly, Jesus Christ is heavenly 1Co 15:47

The contrast in the consequences of the actions of the first Adam and the second Adam
Adam brought death, Jesus Christ brings life Ro 5:15,17; 1Co 15:21-23

Adam brought judgment, Jesus Christ brings justification Ro 5:16,18-19

The assurance this doctrine brings 1Co 15:48-49 See also Php 3:20-21

Martin H. Manser, Dictionary of Bible Themes: The Accessible and Comprehensive Tool for Topical Studies (London: Martin Manser, 2009).