Romans 6:16-17 - Know ye not, that to whom ye yield yourselves servants to obey, his servants ye are to whom ye obey; whether of sin unto death, or of obedience unto righteousness?But God be thanked, that ye were the servants of sin, but ye have obeyed from the heart that form of doctrine which was delivered you. (Verses like Romans 6:16)
John 8:34 - Jesus answered them, Verily, verily, I say unto you, Whosoever committeth sin is the servant of sin. (Verses like John 8:34)