“Whom I have sent unto you for the same purpose, that he might know your estate, and comfort your hearts;”
King James Version (KJV)
Matthew Henry's Concise Commentary
4:7-9 Ministers are servants to Christ, and fellow-servants to one another. They have one Lord, though they have different stations and powers for service. It is a great comfort under the troubles and difficulties of life, to have fellow Christians caring for us. Circumstances of life make no difference in the spiritual relation among sincere Christians; they partake of the same privileges, and are entitled to the same regards. What amazing changes Divine grace makes! Faithless servants become faithful and beloved brethren, and some who had done wrong, become fellow-workers of good.
“But this is that which was spoken by the prophet Joel;”