What does the Bible say about substitution in Christ?

Substitution is central to the doctrine of the atonement in the Bible. In 2 Corinthians 5:21, we read that God made Christ, who knew no sin, to be sin for us. This signifies that Christ took upon Himself the guilt and punishment that rightfully belonged to sinners, thus satisfying God's justice. This is a profound expression of grace, whereby through Christ's substitution, believers are declared righteous. It is essential for understanding the entire plan of salvation, showing how God's justice and mercy harmonize.