Theophylact of Ohrid
Catena Aurea · Lukasevangelium 16
And the lord commended the unjust steward, because he had done wisely: for the children of this world are in their generation wiser than the children of light. And I say unto you, Make to yourselves friends of the mammon of unrighteousness; that, when ye fail, they may receive you into everlasting habitations. He that is faithful in that which is least is faithful also in much: and he that is unjust in the least is unjust also in much. If therefore ye have not been faithful in the unrighteous mammon, who will commit to your trust the true riches? And if ye have not been faithful in that which is another man’s, who shall give you that which is your own? No servant can serve two masters: for either he will hate the one, and love the other; or else he will hold to the one, and despise the other. Ye cannot serve God and mammon.
Thus then hitherto He has taught us how faithfully we ought to dispose of our wealth. But because the management of our wealth according to God is no otherwise obtained than by the indifference of a mind unaffected towards riches, He adds, No man can serve two masters.