Romans 6:16
God forbid! Know ye not, that to whom ye present yourselves servants to obedience, his servants ye are whom ye obey? either of sin unto death, or of obedience unto righteousness?
John 8:34
Jesus answered them, Verily, verily I say unto you, whosoever maketh a practice of sin, is the servant of sin.
2 Peter 2:19
promising them liberty, while they themselves are the slaves of corruption: for by whom any one is vanquished, by him he is also enslaved.
Matthew 6:24
No one can serve two masters; for either he will hate the one, and love the other; or at lest he will be attached to the one, and neglect the other: ye cannot serve God and mammon:
Romans 6:12-13
Let not sin therefore reign in your mortal body, to obey it in the lusts thereof.
Romans 6:17
But thanks be to God, that ye who were servants of sin, have obeyed from the heart that form of doctrine which was delivered to you:
Romans 6:19-23
I speak after the manner of men, because of the infirmity of your flesh: as ye have yielded your bodies servants to impurity and iniquity to work iniquity; so now present your bodies servants to righteousness, unto holiness.