1 Peter 2:24
and He Himself bore our sins in His body on the cross, so that we having died to sin might live to righteousness; for by His wounds you were healed.
When mankind fell, sin entered the world like a demonic virus bringing death to all things. Romans 7 refers to this spiritual virus as “the law of sin and death.” When sin entered mankind, it changed our very nature, and humanity became slaves to its power and its condemnation. This horrible spiritual virus reigned. The only solution was death and resurrection. Sin diseased humanity and the whole fallen order was assumed by Christ into His person so that through His death, and resurrection a whole new humanity and a whole new world order could rise from the dead. Christ did not heal our sin-sick fallen self by standing apart from us, diagnosing our sickness, prescribing medicine for us to take, and then going away to leave us to get better by obeying his instructions as an ordinary doctor might. No, He became the sin diseased patient! He became all of sin diseased humanity which was in need of redemption and healing, and in dying and rising again for us, as us; crucifying and burying sin-sick mankind our humanity was healed in Him that we might now in union with Him and the power of His resurrection, live to righteousness.