Romans 6:16

2 Peter 2:19 NIV
They promise them freedom, while they themselves are slaves of depravity—for “people are slaves to whatever has mastered them.”

John 8:34 NIV
Jesus replied, “Very truly I tell you, everyone who sins is a slave to sin.

Joshua 24:15 NIV
But if serving the Lord seems undesirable to you, then choose for yourselves this day whom you will serve, whether the gods your ancestors served beyond the Euphrates, or the gods of the Amorites, in whose land you are living. But as for me and my household, we will serve the Lord.”

Matthew 6:24 NIV
“No one can serve two masters. Either you will hate the one and love the other, or you will be devoted to the one and despise the other. You cannot serve both God and money.

Romans 6:12-13 NIV
Therefore do not let sin reign in your mortal body so that you obey its evil desires. Do not offer any part of yourself to sin as an instrument of wickedness, but rather offer yourselves to God as those who have been brought from death to life; and offer every part of yourself to him as an instrument of righteousness.