Jn 8:34 Jesus answered them, Verily, verily, I say unto you, Whosoever committeth sin is the servant of sin. What is a servant of sin ? Its first and foremost a unbeliever, and we all by nature are servants of sin/unbelievers, yes by nature we are in servitude, slavery to unbelief, to disobedience, just like the children of disobedience Eph 2:2 Wherein in time past ye walked according to the course of this world, according to the prince of the power of the air, the spirit that now worketh in the children of disobedience: That word disobedience is the same word unbelief here Rom 11:32 For God hath concluded[consigned,imprisoned] them all in unbelief and or disobdience, that he might have mercy upon all. So Elect and non elect are born prisoners, servants of unbelief, disobedience which is I.obstinacy, obstinate opposition to the divine will, Its translated unbelief in Rom 11:30,32;Heb 4:6,11 ! I know many believe that to be a servant of sin we must be fornicators, theives, or drunkards and so on, though practicing those things are servitude to sin, yet truth be told, simple unbelief is servitude to sin. Understand, er can be ever so moral, religious and sincere, have outstanding character, and yet dont believe the True Gospel by a revelation of the Spirit, we are servants of sin/unbelief. Remember when Paul wrote of himself in Phil 3:4-6 Though I might also have confidence in the flesh. If any other man thinketh that he hath whereof he might trust in the flesh, I more: 5 Circumcised the eighth day, of the stock of Israel, of the tribe of Benjamin, an Hebrew of the Hebrews; as touching the law, a Pharisee; 6 Concerning zeal, persecuting the church; touching the righteousness which is in the law, blameless. Now notice Vs 6 when he speaks of his zeal and blamelessness touching the righteousness which is in the Law, now all that time he was a servant of sin, because of ignorance and unbelief 1 Tim 1:13 13 Who was before a blasphemer, and a persecutor, and injurious: but I obtained mercy, because I did it ignorantly in unbelief. The exact same is true of the religious and zealous jews he wrote of here Rom 10:2-3, those zealous jews in the jews religion as Paul calls it Gal 1:13-14 13 For ye have heard of my conversation in time past in the Jews' religion, how that beyond measure I persecuted the church of God, and wasted it: 14 And profited in the Jews' religion above many my equals in mine own nation, being more exceedingly zealous of the traditions of my fathers. Those jews were servants of sin, because of their unbelief !