Ephesians 4:25

"Therefore, having put away falsehood, let each one of you speak the truth with his neighbor, for we are members one of another."

Understanding the ninth commandment's legal context and its prohibition against normal lies and any speech or act that harms another person helps us see how to apply this law properly. For instance, it helps us explain why individuals such as the Egyptian midwives and Rahab are praised in Scripture instead of condemned (Ex. 1:15–21; Josh. 2; Heb. 11:31; James 2:25). If the ninth commandment prohibits speech that harms others, it seems that these women actually followed the intent of this statute even when they deceived others. Knowing that the soldiers wanted to hurt the Israelites, they were not forthright when these men came calling. If they had been, the Israelite slaves and spies would have suffered harm.

Of course, the settings in which such deception may be permissible are few, limited to times of war or times when one or more people are seeking to harm an innocent person. Nevertheless, knowing that the ninth commandment prohibits speech that inflicts harm on others does help us understand why lying in general falls under what is prohibited by this law. If I am caught in my wickedness and lie about it, I am first of all harming myself because God desires "truth in the inward being" (Ps. 51:6), and He remains angry with those who do not acknowledge the truth of their sin and repent (7:12–16). Moreover, my lies hurt other people. Failing to acknowledge my sin and lying to cover it up keeps fellow believers from being able to bear my burden with me and fulfill the law of Christ (Gal. 6:1–2). My lies can also lead to trouble for others if they make decisions based on the falsehoods I have told them.

Seeing that the ninth commandment prohibits speech that harms other people also explains why question and answer 112 of the Heidelberg Catechism list gossip as one of the sins that is contrary to this statute. Spreading incomplete information or unconfirmed rumors can destroy another person's reputation, as can revealing secrets about an individual to others who have no reason to know said information.

Indeed, the tongue is a powerful instrument that can cause great good or ill. There is little wonder, then, that God's law restrains the small flames of our tongues in the ninth commandment. Used rightly, fire brings the blessing of warmth and well-being. Used wrongly, fire destroys lives. So it is with our tongues (James 3:1–12).

Coram Deo

Matthew Henry writes, "Truth is a debt we owe to one another; and, if we love one another, we shall not deceive one another." Christians must be known for their love of the truth and the trustworthiness of their speech. When we lie and gossip, we bear false witness to the God of truth who has transformed our hearts to love and serve Him. May we seek to tell the truth to friends, family, fellow church members, and coworkers. May we also repent when we fail to do so.

For Further Study