Albert Barnes Commentary John 8:34

"Jesus answered them, Verily, verily, I say unto you, Every one that committeth sin is the bondservant of sin." — John 8:34 (ASV)

Whosoever committeth sin. In this passage Jesus shows them that he did not refer to political bondage, but to the slavery of the soul to evil passions and desires.

Is the servant. Is the slave of sin. He is bound to it as a slave is to his master.