Q. What is forbidden in the ninth commandment?

A. The ninth commandment forbiddeth whatsoever is prejudicial to truth, or injurious to our own, or our neighbor’s, good name.

Westminster Shorter Catechism, Q&A 78

In the third chapter of the book of James, the brother of our Lord has much to say about the power of the tongue and the damage we can do to others through our speech.  The tongue may seem small (in comparison to the rest of our bodies), but like a horse’s bridle or a ship’s rudder, James warns us not to let the tongue’s small size fool us in regard to its power. As James says in verse 5, “The tongue is a small member, yet it boasts of great things.” James goes on to lament, “How great a forest is set ablaze by such a small fire! And the tongue is a fire, a world of unrighteousness. The tongue is set among our members, staining the whole body, setting on fire the entire course of life, and set on fire by hell” (v. 6).

According to James, the tongue reveals the sin that is hidden deep in the heart. Like nothing else can, the words we speak reveal the extent of our inherent unrighteousness. To make matters worse, our sinfulness is so entrenched that James can say that “no human being can tame the tongue. It is a restless evil, full of deadly poison. With it we bless our Lord and Father, and with it we curse people who are made in the likeness of God. From the same mouth come blessing and cursing” (vv. 8–9).

The words in the third chapter of James clearly reflect the ninth commandment of the law of God (Ex. 20:16), wherein we are commanded not to bear false witness against our neighbor. And the Westminster Shorter Catechism describes what is required by the ninth commandment in question 78. When my tongue reveals audibly how I feel about my neighbors in my heart, inevitably, I will either curse them or speak ill of them. Like the default setting in a computer program, sinful human nature’s default setting is to speak ill of our neighbor, cursing them, as James says, or else speaking untruthfully of them as mentioned in the commandment.

The warning from James and the words of the ninth commandment are intended to do two things. The first thing the reminder about our own sinful tongue is intended to do is to show us just how sinful we truly are. Imagine, for a moment, that everything you’ve said (or even worse, thought) this day were tape-recorded and then played back before all those who were mentioned in your conversations. While there might be a few words of blessing, your words more than likely cursed someone created in God’s image and were often spoken to belittle, accuse, or otherwise speak ill of them. The realization of the fact that we are law-breakers (remember, it is James who also reminds us that if we break God’s law in but one place, we are guilty of having broken all of it, 2:10) should drive us to Christ to seek forgiveness for our sins (Gal. 3:19–25;
1 John 2:1–2).

The second thing the Law is intended to do is to show us what God expects of us now that we are Christians whose sins have been forgiven through the shed blood of Jesus Christ. As the old Reformed theologians used to speak, the Law is both the teacher of sin and the rule of gratitude. God expects us to cease cursing our neighbor and speaking ill of them. After all, self-control is one of the fruits of the Spirit (Gal. 5:23).  Having shown us how sinful we are, the ninth commandment now shows us what God expects of us. Indeed, the Holy Spirit works in us the desire not to curse our neighbors or speak ill of them, and He gives us the power to guard our words.

Nevertheless, because indwelling sin remains within us (Gal. 5:17), we’ll keep on cursing our neighbors and speaking ill of them in open violation of the law of God. This is why we take heart in knowing that we are saved by grace through faith (Eph. 2:8), and why we should take great comfort in the fact that Jesus Christ (whose righteousness is imputed to us through faith) never once cursed His neighbor, nor spoke ill of them.

It is only by considering the gravity of our sin and the wonder of God’s grace (especially in the fact that Jesus died for all those times we’ve cursed our neighbor), that the power of the tongue can be controlled. While we will never stop sinning until we die or the Lord returns (whichever comes first), the very fact that God considers us in Christ as though we had never cursed our neighbors and ruined their reputations with our words becomes the means through which God restrains our sinfulness. When we consider the way Jesus spoke, and when we consider how God views our neighbors, only then do the words that have the power to destroy entire forests become words of blessing.

For Further Study