This simple sentence sums up so well what the Gospel is all about. We have failed to keep God’s Laws and Commandments (but Christ did) and for this failure, we should be put to death (Christ was) and our death would not make up for our failure (Christ’s did). John Piper talks about this more fully in the September/October issue of Modern Reformation magazine. here’s an excerpt.
What God Requires, Christ Provides
Justification cannot come through the law (see Gal. 2:21; Acts 13:38-39). Each of us-every single human being (see Rom. 3:10-12, 19-20)-has failed to do what God’s law requires of us (Gal. 3:10; 6:13; cf. James 2:10). But to understand what God requires, we must see what Christ provides. In his mercy, God has provided his Son as a twofold substitute for us. Both facets of Christ’s substitution are crucial for our becoming right with God. These facets are grounded in the twin facts that (1) we have failed to keep God’s law perfectly, and so we should die; but (2) Jesus did not fail?he alone has kept God’s law perfectly (see Heb. 4:15) ?and so he should not have died. Yet in his mercy God has provided in Christ a great substitution?a “blessed exchange”?according to which Jesus can stand in for us with God, offering his perfect righteousness in place of our failure and his own life’s blood in place of ours. When we receive the mercy God offers us in Christ by faith (see Acts 16:31; 1 Tim. 1:15-16; 1 Pet. 1:8-9), his perfection is imputed?or credited or reckoned?to us and our sinful failure is imputed?or credited or reckoned?to him. And thus Jesus’ undeserved death pays for our sin (see Mark 10:45; 1 Tim. 2:5-6; Rev. 5:9); and God’s demand for us to be perfectly righteous is satisfied by the imputation or crediting of Christ’s perfect righteousness to us. “If justification were through the law, then Christ died for no purpose” (Gal. 2:21). But “God has done what the law … could not do” (Rom. 8:3).
Read the full article here: What God Requires, Christ Provides by John Piper with Justin Taylor