Albert Barnes on 1 Corinthians 16:18

For they have refreshed my spirit. By their presence and conversation. They have given me information respecting the state of things in the church; and their society has been with me of the most gratifying and cheering kind.

And your's. "By removing," says locke, "those suspicions and fears that were on both sides." By this supplying your absence, they have benefited us both. For Paul gained information of those absent, and they gained in the counsel afforded to them by the apostle."--Bloomfield.

"For they refreshed my spirit by their obliging behaviour and edifying conversation, as, I doubt not, they have often refreshed yours by their ministrations among you."--Doddridge. The sense seems to be, that their visit to him would be a benefit to both; would result in imparting comfort, a good understanding, an increase of their mutual attachment, and ultimately a large accession to their mutual joy when they should again meet.

Therefore acknowledge ye them that are such. Receive affectionately; recognise as brethren; cherish, treat kindly all that evince such a spirit. 1Cor 16:15. 1Cor 16:16. The apostle here designs, evidently, that the Corinthians should receive them kindly on their return, and regard with deference and respect the counsel which they might offer, and the message which they might bear from him.

(i) "acknowledge ye them" 1Thes 5:12