I. It is a remarkable story told by the poet Cowper of himself, that, when he was a young man, and living in London, where his companions were not only persons of profligate life, but of low and ungodly principles, they always had a great advantage over him when arguing upon the truth of Christianity by reproaching him with the badness of his own life. In fact, it appears that his life at that time was quite as bad as theirs, and they used to upbraid him for it; telling him that it would be well for him if they were right and he wrong in their opinions respecting the truth of the Gospel; for if it were true, he certainly would be condemned upon his own showing. These men, like the unjust steward in the parable, had at least the merit of acting wisely upon their own view of the matter; they made the mammon of unrighteousness that is, the riches and enjoyments of the world serve their turn for all that they believed them capable of yielding. And therefore Christ makes their conduct a reproof to Christians, who do not make the world yield to them that fruit which, according to their professed belief, it might afford them.
II. The lesson which the parable of the unjust steward is designed to teach us is, that nothing is more unworthy, nothing more ruinous, than to be a Christian by halves; to begin to build, and not be able to finish. Salt is good, but the salt that has lost its savour is good neither for the land nor yet for the dunghill, but men cast it out; and even so vile and worthless is that Christian, in name only, who does not live according to his own principles but in defiance of them who, with a journey to an eternal state opened before him, plays away his time on the road, and makes no provision for the end of his pilgrimage.
III. This one parable of our Lord's is to many a stumbling-block and to few so useful as it ought to be. To make to ourselves friends of the mammon of unrighteousness, an English reader naturally understands to mean to make the mammon of unrighteousness, or unrighteous riches, our friends; whereas the real meaning of the words is: "Make to yourselves friends with, or by, the mammon of unrighteousness; that is, so use the riches and other advantages of this world that they may gain you friends hereafter friends that will stand by you, when the riches themselves have perished. I need hardly add what these friends are the record of good done upon earth, of misery relieved, of folly enlightened, of virtue encouraged and supported the record of theirthankful voices, who, having received from us good things in this world, shall welcome us with thanks and blessings, when we all stand together before Christ's judgment-seat.
T. Arnold, Sermons,vol. ii., p. 205.