Christ the Substitution.

“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.” 2 Corinthians 5:21

Suggested Further Reading: 1 Peter 2:18-25

Of this God in Christ, our text says that he knew no sin. It does not say that he did not sin; that we know: but it says more than that; he did not know sin; he knew not what sin was. He saw it in others, but he did not know it by experience. He was a perfect stranger to it. It is not barely said, that he did not take sin into his heart, but he did not know it. It was no acquantance of his. He was the acquaintance of grief; but he was not the acquaintance of sin. He knew no sin of any kind,—no sin of thought, no sin of birth, no original, no actual transgression; no sin of lip, or of hand, did ever Christ commit. He was pure, perfect, spotless; like his own divinity, without spot or blemish, or any such thing. This gracious person, is he who is spoken of in the text. He was a person utterly incapable of committing anything that was wrong. It has been asserted lately, by some ill-judged one, that Christ was capable of sin. I think it was Irving who started some such idea, that if Christ was not capable of sinning, he could not have been capable of virtue. “For,” say they, “if a man must necessarily be good, there is no virtue in his goodness.” Away with their ridiculous nonsense! Is not God necessarily good? And who dares deny that God is virtuous? Are not the glorified spirits in heaven necessarily pure? And yet are they not holy because of that very necessity? Are not the angels, now that they are confirmed, necessarily faultless? And shall any one dare to deny angelic virtue! The thing is not true; it needs no freedom in order to create virtue. Freedom and virtue generally go together; but necessity and virtue are as much brother and sister as freedom and virtue. Jesus Christ was not capable of sin.

I am crucified with Christ: nevertheless I live; yet not I, but Christ lives in me: and the life which I now live in the flesh I live by the faith of the Son of God, who loved me, and gave himself for me. I do not nullify the grace of God: for if righteousness comes by the law, then Christ is dead in vain.
(Gal 2:20-21)

Taken from Sermon no. 141-142 by Charles Spurgeon
19 July (1857)