I speak not by commandment
Either of God, who has not fixed the certain times when, or certain sums which persons are to give, and other circumstances, which are left to discretion; but in general has signified it as his will, that those in necessity are to be relieved by such who are in ability to do it: or as an apostle, he did not speak in an imperious manner, extorting from them a collection, or laying his apostolical injunctions upon them to make one; he did not go about to force or oblige them to it, for men in such cases must act willingly, and what they do, must do of their own accord with cheerfulness, and not through constraint or grudgingly:
but by occasion of the forwardness of others;
or "through carefulness for others"; what moved the apostle to propose this matter to the Corinthians, and exhort them to it, were either the forwardness of the Macedonians, cheerfully contributing in the midst of their poverty, and their urgent solicitations that the same good work might go on elsewhere, or else the very great care and concern that he himself had for the poor saints at Jerusalem: it was not therefore to show his apostolical authority, that he sent Titus to them to finish this service; but he was stirred up hereunto, partly by the bounty and solicitations of others, and partly by bowels of compassion within himself, and concern in his own mind for the poor saints; and also, as he adds,
to prove the sincerity of your love;
to God, to Christ, to his ministers, and to the saints, particularly the poor; that their love might appear to be true, genuine, hearty, and real to others, to all men as well as to them the apostles.