Augustine of Hippo
Catena Aurea · Matthäusevangelium 6
No man 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.
(Serm. in Mont. ii. 14.) Whoso serves mammon, (that is, riches,) verily serves him, who, being for desert of his perversity set over these things of earth, is called by the Lord, The prince of this world. Or otherwise; who the two masters are He shews when He says, Ye cannot serve God and mammon, that is to say, God and the Devil. Either then man will hate the one, and love the other, namely God; or, he will endure the one and despise the other. For he who is mammon’s servant endures a hard master; for ensnared by his own lust he has been made subject to the Devil, and loves him not. As one whose passions have connected him with another man’s handmaid, suffers a hard slavery, yet loves not him whose handmaid he loves. But He said, will despise, and not will hate, the other, for none can with a right conscience hate God. But he despises, that is, fears Him not, as being certain of His goodness.