He subsequently elaborated on this commandment:
You must not pass along false rumors. You must not cooperate with evil people by lying on the witness stand.
You must not follow the crowd in doing wrong. When you are called to testify in a dispute, do not be swayed by the crowd to twist justice. And do not slant your testimony in favor of a person just because that person is poor.Exodus 23:1-3, New Living Translation
The core principle is this: Make sure that what you say is accurate. Don’t say something just because it’s popular or interesting or because you think it will advance a worthy cause.
The brother of Jared said that Jesus Christ is a God of truth, and that He cannot lie (Ether 3:12, see also Deuteronomy 32:4). Enos said that he “knew that God could not lie” (Enos 1:6, see also 1 Samuel 15:29). So God also follows this principle: He does not say things that aren’t true.
Under the law of Moses, the risk of false testimony was mitigated by requiring multiple witnesses for any conviction:
One witness shall not rise up against a man for any iniquity, or for any sin, in any sin that he sinneth: at the mouth of two witnesses, or at the mouth of three witnesses, shall the matter be established.Deuteronomy 19:15
This is a good practice for each of us in our personal efforts to distinguish truth from error: Look for multiple corroborating sources of truth. Don’t take one person’s word for it.
Elder David A. Bednar taught that we bear false witness when our actions don’t match our words:
A public statement of love when the private actions of love are absent at home is hypocrisy—and weakens the foundation of a great work. Publicly declaring testimony when faithfulness and obedience are missing within our own homes is hypocrisy—and undermines the foundation of a great work. The commandment “Thou shalt not bear false witness” (Exodus 20:16) applies most pointedly to the hypocrite in each of us.“More Diligent and Concerned at Home,” General Conference, October 2009
And President Gordon B. Hinckley has urged us to avoid speaking negatively about one another:
Be true to yourselves, my dear friends. Be true to one another, your friends and associates. Look for the good in those about you, and emphasize that good. Never go around gossiping about your associates or speaking unkind words concerning them. Such words will only backfire to hurt you. Jehovah has commanded, “Thou shalt not bear false witness” (Ex. 20:16).“Stand True and Faithful,” General Conference, April 2006
Today I will be a true witness. I will corroborate the things I hear before passing them along, particularly when they are dramatic or sensational. I will prioritize truth over desired outcomes. And I will strive to be more aware of the impact of my words on other people.