Jesus as Surety for His People

"To Jesus Christ, to His account, as the one now responsible for the sins of those in whose stead He died, God imputed our sins. Although personally the man Jesus was sinless, the guilt of the others became His own on the cross, indeed, throughout all His life of suffering, by God's imputation of this guilt to Him. God held Jesus responsible for the sins and sinfulness of all the elect, for whom Jesus was the divinely-appointed substitute. God dealt with Him accordingly, cursing and damning Him." 

- David Engelsma, "Gospel Truth of Justification," p. 294 

In the paragraph above, Engelsma is summarizing and paraphrasing what Paul taught in three passages. The first was Galatians 3:13-14: "Christ redeemed us from the curse of the law by becoming a curse for us - for it is written, 'Cursed is everyone who is hanged on a tree' - so that, in Christ Jesus, the blessing of Abraham might come to the Gentiles, so that we might receive the promised Spirit through faith." The second is II Corinthians 5:21: "For our sake He [the Father] made Him [the Son] to be sin who knew no sin, so that, in Him [the Son], we might become the righteousness of God." And, finally, Galatians 2:20: "I have been crucified with Christ. It is no longer I who live, but Christ who lives in me. And the life I now live in the flesh, I live by faith in the Son of God, who loved me and gave Himself for me."

In theology, we say that Jesus gave Himself to be the surety for all those whom the Father had given Him. Or, to use our modern parlance, He became the "co-signor" for us. But that must be understood a little differently. When a person, call him John, co-signs a loan for another person, call him Bob, then John takes upon himself a risk. Bob is promising to repay his loan, but, if he fails, the loan then becomes John's responsibility. However, in the case of the suretyship of Jesus, He agreed to co-sign for the sin debt of His people, even knowing in advance that His people would indeed fail. He didn't just assume a risk; He assumed the certainty that His people would have a sin debt for which He was taking responsibility. Would any merely-human co-signor agree to such a responsibility? 

But notice further that Jesus, as surety, didn't undertake merely the debt of our sins. There was a further imputation, as well. As Paul said to the Corinthians, the redeemed become "the righteousness of God." The redeemed are not brought to some morally-neutral state, but rather we are brought to a positive account of righteousness, His righteousness, so that, as the same Apostle told the Galatians, we live the godly life as Jesus's righteousness is placed in us, by means of faith alone. That is an instantaneous exchange, not the progressive one pretended by Rome and other Pelagian sects. It is done!