"in Christ"

“To say that Jesus is the second Adam ushers us directly to the importance of union with Christ. If ‘in’ Adam we sin and die, so ‘in’ Christ we become righteous and live. In other words, it is all about ‘with and to whom’ we are united. Jesus is the second Adam who, through the whole of his incarnation, incorporates us into his life. The upshot of this is enormous: everything that is Christ’s becomes ours by being united to him. Everything, including wisdom and righteousness and sanctification and redemption, comes to us because we are united to the incarnate one (I Cor. 1:30).

“Emphasizing union with Christ foregrounds a relational theory of the atonement. My own reading of the Reformed thinkers on atonement leads me to contend that many of them deemphasize the relational aspects because they deemphasize ‘union with Christ’ and Christ as the second Adam.”—A Community Called Atonement, p. 59 (emphasis his)