God the Father so loved us that He sent His only begotten Son Jesus Christ. Jesus, the Word, became man, bore our sins in His body on the cross (1 Peter. 2:24), and died in our place, suffering the consequences of the breaking of the Law (1 John 3:4), which is physical death (Rom. 6:23) and spiritual death (Isa. 59:2), that was due us (Isaiah 53:4-6). He became sin on our behalf (2 Cor. 5:21). His sacrifice was a legal substitution for us (1 John 2:2; John 19:30; 1 Pet. 2:24). It was legal since sin is breaking God’s Law (1 John 3:4) and substitutionary since Christ took our punishment (Isaiah 53:4-6) and tasted death for everyone (Heb. 2:9). As a result God’s justice was satisfied and Christian believers are released from eternal punishment (1 Pet. 3:18; Matt. 1:21; 25:46; Rom. 5; 1 John 2:2), and the debt that our sin brings against us has been cancelled (Col. 2:14).
See also Penal Substitutionary Atonement.