"No one can serve two masters. Either he will hate the one and love the other, or he will be devoted to the one and despise the other. You cannot serve both God and Money."
This is a principle that is ignored way too much.
We always think that we can serve as many master as there are hours in the day. We think that we can switch from one to the other like it is nothing. But "no one can serve two masters!" And that means no one! And according to this verse, if you try to serve two masters, you will grow resentful of one or the other.