'Slaves' in the Bible

knowing this, that our old self was crucified with Him, in order that our body of sin might be done away with, so that we would no longer be slaves to sin;

Do you not know that when you present yourselves to someone as slaves for obedience, you are slaves of the one whom you obey, either of sin resulting in death, or of obedience resulting in righteousness?

But thanks be to God that though you were slaves of sin, you became obedient from the heart to that form of teaching to which you were committed,

and having been freed from sin, you became slaves of righteousness.

I am speaking in human terms because of the weakness of your flesh. For just as you presented your members as slaves to impurity and to lawlessness, resulting in further lawlessness, so now present your members as slaves to righteousness, resulting in sanctification.

For when you were slaves of sin, you were free in regard to righteousness.

For such men are slaves, not of our Lord Christ but of their own appetites; and by their smooth and flattering speech they deceive the hearts of the unsuspecting.