Redemption is the completed act of buying back. In Christian usage it names both the historical event of Christ’s death and resurrection and the ongoing application of that event to individual lives and to the world.

The New Testament writers draw on the older Hebrew imagery of the kinsman-redeemer and of Israel’s deliverance from Egypt. They add the language of ransom and of slavery: human beings are sold under sin; Christ pays the price that sets them free. Paul can speak of believers as having been bought with a price; the book of Revelation pictures the redeemed as those purchased for God from every tribe and nation. The cost is not abstract. It is the life of the Son.

Later theology worked out the implications. Some traditions stress penal substitution—Christ bearing the penalty that justice required. Others emphasize Christus Victor—Christ defeating the powers of evil. Still others highlight the moral influence of the cross, its power to awaken love and repentance. Most classical accounts hold these strands together rather than choosing one exclusively.

Redemption is never presented as automatic. Faith, repentance, and baptism mark the entrance into the redeemed community, and the full effects await the final resurrection. Until then the redeemed live between the already and the not yet, tasting freedom while still contending with the old order.