Do not be a witness against your neighbor without cause, for would you deceive with your lips? (Proverbs 24:28)
The connotation of this proverb appears to simply be, "mind your own business." We are not to speak against our neighbors without the certainty that they have violated the laws of the land. The emphasis on "certainty." To speak without undeniable evidence is to deceive with your lips. To speak to anyone other than a proper authority is likewise deceptive. It is nothing more than gossip. If I suspect that my neighbor is doing something wrong, depending on that wrong, I have one of two options: I can go to my neighbor or to an appropriate authority. We are not to speak against our neighbors because of differing opinions or preferences. To do so is deception. If you have a difference of opinions or preferences, discuss them with your neighbor. Do not discuss them against your neighbor. Another proverb gives the solution, "Debate your case with your neighbor, and do not disclose the secret to another."