Matthew Poole and continuators on 2 Corinthians 5:21

21 For he hath made him to be sin for us, who knew no sin , that we might be made the righteousness of God in him .

Christ knew no sin, as he was guilty of no sin; which of you (saith he Iob. 8.46.) convinceth me of sin? 1 Pet. 2.21, 22, 24. He did no sin, nor was guil[illegible: 1 letter] sound in his mouth. But God made him to be sin for us; He was numbred amongst the transgressours, Isai. 53.6, 12. Our sins were reckoned to him; so as though personally he was no Sinner, yet by imputation he was, and God dealt with him as such; Or he was made a Sacrifice for our sins, a Sin-offering; so answering the Type in the Law, Lev. 4.3.25.29. & 5, 6. & 7.2.

that so his righteousness might be imputed to us, and we might be made righteous with such a righteousness as those souls must have whom God will accept. As Christ was not made sin by any sin inherent in him, so neither are we made righteous by any righteousness inherent in us, but by the righteousness of Christ imputed to us; as he was a Sinner by the sins of his people reckoned and imputed unto him.

Marginal references: Gal. 3.13. 1 Joh. 3.5.; Rom. 1.17.