What does substitution mean in the context of the gospel?

The concept of substitution is vital to the gospel message; it denotes that Jesus Christ died in our place, a theological truth deeply rooted in the Old Testament sacrificial system. Jesus, as the perfect Lamb of God, took upon Himself the punishment that we deserved for our sins. Isaiah 53:5 proclaims, 'But he was wounded for our transgressions, he was bruised for our iniquities; the chastisement of our peace was upon him; and with his stripes we are healed.' Thus, understanding substitution clarifies how we achieve reconciliation with God—not through our works, but through faith in Christ’s atoning sacrifice.