8:16-24 The apostle commends the brethren sent to collect their charity, that it might be known who they were, and how safely they might be trusted. It is the duty of all Christians to act prudently; to hinder, as far as we can, all unjust suspicions. It is needful, in the first place, to act uprightly in the sight of God, but things honest in the sight of men should also be attended to. A clear character, as well as a pure conscience, is requisite for usefulness. They brought glory to Christ as instruments, and had obtained honour from Christ to be counted faithful, and employed in his service. The good opinion others have of us, should be an argument with us to do well.
18. the brother, whose praise is in the gospel—whose praise is known in connection with the Gospel: Luke may be meant; not that "the Gospel" here refers to his written Gospel; but the language implies some one well known throughout the churches, and at that time with Paul, as Luke then was (Ac 20:6). Not a Macedonian, as appears from 2Co 9:4. Of all Paul's "companions in travel" (2Co 8:19; Ac 19:29), Luke was the most prominent, having been his companion in preaching the Gospel at his first entrance into Europe (Ac 16:10). The fact that the person here referred to was "chosen of the churches" as their trustee to travel with Paul in conveying the contribution to Jerusalem, implies that he had resided among them some time before: this is true of Luke, who after parting from Paul at Philippi (as he marks by the change from "we" to "they," Ac 16:11) six years before, is now again found in his company in Macedonia. In the interim he had probably become so well known that "his praise was throughout all the churches." Compare 2Co 12:18; Phm 24. He who is faithful in the Gospel will be faithful also in matters of inferior importance [Bengel].