What are we to understand by His being made sin? We have partly anticipated the meaning of the words:—“Made Him to be sin.” [Reader,] if Christ takes the sinner’s place, He must bear the sinner’s sins and punishment which the sinner ought to have borne for his disobedience to, and transgression of the law of God. Christ is made sin by imputation. He was not a sinner by nature, but sin was charged upon Him, as He stood in the stead of His people. My own [thought] is, that the doctrine of imputation arises out of union. To illustrate what I mean, take the following words: “For as by one man’s disobedience many were made sinners, so by the obedience of one shall many be made righteous” (Romans 5:19).

Union with Adam makes us sinners with him. Union with Christ makes us righteous with Him.