2 Corinthians 5:21 Meaning

19To wit, that God was in Christ, reconciling the world unto himself, not imputing their trespasses unto them; and hath committed unto us the word of reconciliation.

20Now then we are ambassadors for Christ, as though God did beseech you by us: we pray you in Christ's stead, be ye reconciled to God.

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