'Masters' in the Bible

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.

And as they were loosing the colt, its masters said to them, Why loose ye the colt?

But He said to them, "The kings of the Gentiles are their masters, and those who exercise authority over them are called Benefactors.