John Calvin on 2 Corinthians 8:6

6. That we should exhort Titus. Now this is an exhortation that is of greater force, when they learn that they are expressly summoned to duty. “Quand ils oyent qu’on les somme nommeement et presentement de faire leur droit;” — “When they hear that they summon them expressly and presently to do their duty.” Nor was it offensive to the Macedonians, that he was desirous to have the Corinthians as partners in beneficence. In the mean time an apology is made for Titus, that the Corinthians may not think that he pressed too hard upon them, as if he had not confidence in their good disposition. For he did that, from having been entreated, and it was rather in the name of the Macedonians, than in his own.