(KJV) 2 Corinthians 8:18
18 And we have sent with him the brother, whose praise is in the gospel throughout all the churches; 19 And not that only, but who was also chosen of the churches to travel with us with this grace, which is administered by us to the glory of the same Lord, and declaration of your ready mind:
(KJV) 2 Corinthians 8:22
22 And we have sent with them our brother, whom we have oftentimes proved diligent in many things, but now much more diligent, upon the great confidence which I have in you
This brother seems to be well recommended by the churches as well as the apostle Paul. Who is this brother?