Atonement.

atonement [əˈtəʊnmənt]

n

1. satisfaction, reparation, or expiation given for an injury or wrong

2. (Christian Religious Writings / Theology) (often capital) Christian theol

a.  the reconciliation of man with God through the life, sufferings, and sacrificial death of Christ

b.  the sufferings and death of Christ

[from Middle English phrase at onement in harmony] (The Free Dictionary.)