The Ministry of Reconciliation
2 Corinthians 5:18-19 is a wonderful short reminder in God's Word of the grace that the Lord has shown us who believe on Jesus Christ as our Savior, and the Good News we have to share about that grace. Here are those verses in context (2 Corinthians 5:16-21):
Wherefore henceforth know we no man after the flesh: yea, though we have known Christ after the flesh, yet now henceforth know we him no more. Therefore if any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new.
And all things are of God, who hath reconciled us to himself by Jesus Christ, and hath given to us the ministry of reconciliation; To 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.
Now 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. 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.
On verse 5:18, commentaries say the "all things" spoken of are the "all things" that have become new mentioned in the previous verse.
2 Corinthians 5:18-20. And all things, &c. — These new things are all of God, the author of them, considered in this view as reconciling us to himself — Removing our carnal mind, which was enmity against him, and taking us into his favour; by Jesus Christ .
David Wilkerson, The Ministry of Reconciliation: