Romans 6:16 in the WEB version says: “Don’t you know that when you present yourselves as servants and obey someone, you are the servants of whomever you obey; whether of sin to death, or of obedience to righteousness?”
And in the Williams version it says: “Do you not know that when you habitually offer yourselves to anyone for obedience to him, you are slaves to that one whom you are in the habit of obeying, whether it is the slavery to sin whose end is death or to obedience whose end is right-doing?”
Presenting ourselves to obey and serve makes us a slave. It is even crazier that the Williams version has even habits as undesirable so much so that we are slaves to them. To put it simply habitual obedience makes us slaves. What habit or regular sin is holding us back and keeping us from slavery to righteousness? We need to form better habits. We need to be habitual obedient to righteousness.