John Chrysostom

"And we have sent with them our brother." Behold, again he adds yet another, and him also with an encomium; both his own judgment, and many other witnesses [to him]. "Whom," saith he, "we have many times proved earnest in many things, but now much more earnest." And having praised him from his own good works, he extols him also from his love towards them; and what he said of Titus, that "being very earnest he went forth of his own accord;" this he says of this person also, saying, "but now much more earnest;" laying up beforehand for …

Homily 18 on 2 Corinthians ↗

Theophylact of Ohrid

He adds yet another, calling him a brother and commending him on the basis of trial and judgment, as a man zealous in many things and having proved himself such many times. To elevate speech in this way is characteristic of praise. But now, he says, he has become even more zealous, as if in the hope that you will offer a more generous alms, which he serves.

Commentary on 2 Corinthians ↗

Thomas Aquinas

Then when he says, "And with them we are sending our brother," he deals with the third messenger, namely, Apollos, and he does two things. First, he commends him for his diligence, when he says, whom, namely, Apollos, we have often tested and found earnest in many matters for your salvation, but who is now more earnest than ever. For as is apparent above, Apollos was the first one after the Apostle to preach to the Corinthians: "I planted, Apollos watered, but God gave the growth" (1 Cor. 3:6). …

Commentary on 2 Corinthians ↗