24 ¶ Whoso is partner with a thief hateth his own soul: he heareth cursing, and bewrayeth it not.
2 Corinthians 8:23 defines partner as a fellowhelper, in case any of you didn’t know it was, in this context, a partner in crime. Bewrayeth means to give testimony to something that is trying to be concealed, to give something up, as in Psalm 27:16 or Matthew 27:73. In one case it is having the ointment that is on your hand revealed by its smell or Peter’s guilt exposed due to the dialect he speaks. Betray, on the other hand, carries with it the meaning of willfully turning someone in, of giving someone up to the authorities.
The partner to the thief shares in the thief’s sin and doesn’t give up the deed even when he hears the victim cursing the thief. The point here is that the person who is an accomplice to sin is as bad as the person initiating the sin. You can’t run with people intent on committing sin and not be one of them, and not share in their guilt. In fact, you will even go so far as to help conceal their crime.
An important thing to remember from this Proverb is that you are a partner in sin if you hear about it and yet say nothing to the thief, take no action. The Christian, when they are aware of sin in the congregation or they perceive that there has been a sin committed, must speak up, preferably to the sinner first, and not hold their peace, lest they be an accomplice to the sin.
Doctrinally, this is true as well.
2 John 9 Whosoever transgresseth, and abideth not in the doctrine of Christ, hath not God. He that abideth in the doctrine of Christ, he hath both the Father and the Son. 10 ¶ If there come any unto you, and bring not this doctrine, receive him not into your house, neither bid him God speed: 11 For he that biddeth him God speed is partaker of his evil deeds.
The Christian who sees sin in the congregation or who hears heresy must speak up. Some fundamentalist churches have been accused of harboring sex offenders and abusive people, even malignant psychopaths, because when their evil deeds were discovered a Pastor refused to do anything about it or to even acknowledge the sin. This has harmed the faith of a great many former independent Baptists. There are even Facebook groups dedicated to survivors of abuse in fundamental Baptist churches and in their schools. If you see a wrong being done and you do nothing or say nothing then you are a partner to the sinner.
It is your business. You have no excuse not to help a brother or sister you think is heading the wrong way by speaking to them and you certainly have no excuse keeping your mouth shut when you see blatant sin or hear obvious heresy. To say nothing makes you a partner in crime and, like the sinner, you are showing contempt for your own soul. How many people, usually children and young women, have had their faith in Christ destroyed by an evil person in their own congregation and the so called Christians who stood by knowing something wasn’t right but saying nothing, making them accomplices to the awful crime?
So, take from this Proverb that the person who knows the thief and what he did but says nothing about the theft is as guilty of the theft as the first person, especially if that theft includes the faith of an innocent and helpless child.