"What is the Ninth Commandment?"
God's Ninth Commandment in the Law of Moses reads: "You shall not bear false witness against your neighbor" (Exo 20:16). The commandment is a general prohibition against lying. More specifically, prohibits saying or doing anything that slanders the character of another, whether publicly or in a court of law. Let us consider the following implications.
First, God commands all people to love the truth. We must not lie, misrepresent ourselves, or vilify others. Christians, especially, should abstain from lying, which is inconsistent with their new nature in Christ (2Th 2:10, Rev 14:5, Col 3:9). The devil is "the father [the originator] of lies," and his work continues in the mouth of the unbelievers who are under his power (John 8:44). Lying is certainly a serious sin against God, for in the Judgment, those who "love and practice" lying, will suffer the same sentence as "sorcerers... the sexually immoral... murderers, and idolaters" (Rev 22:15).
Secondly, Exodus 23:1-7 amplifies the Ninth Command with this clarification: "You shall not spread a false report... nor shall you bear [a false] witness in a lawsuit." We must not willfully give a false report or testimony with the intent to harm and abuse the character of another. To bear false witness in court proceedings is to hold the court "in contempt," and serious penalties follow (Deut 19:18-19). If you "take the stand," tell the truth and you shall have God as your defense.
Finally, other Scriptures shed further light on the subject. "The Lord hates... a false witness who breathes out lies" (Pro 6:16-19), and such "will not go unpunished" (Pro 19:5). "Whoever speaks the truth gives honest evidence, but a false witness utters deceit" (Pro 12:17). "For out of the heart come[s]... false witness [which] defile[s] a person" (Mat 15:19-20). Lying and bearing false witness dishonors God and injures our neighbor. It contradicts the "law of love," for it harms rather than helps. Let us consider a better way.
The Apostle Peter offers this antidote against deceitfulness and a prescription for a happier life: "Finally, all of you, have unity of mind, sympathy, brotherly love, a tender heart, and a humble mind. Do not repay evil for evil or reviling for reviling, but on the contrary, bless, for to this you were called, that you may obtain a blessing. For 'Whoever desires to love life and see good days, let him keep his tongue from evil and his lips from speaking deceit; let him turn away from evil and do good; let him seek peace and pursue it'" (1Pe 3:8-11).
–Pastor Scott (www.askpastorscott.com)