The ninth commandment says not to give false testimony against your neighbor. It’s about more than lying in court. Lying is out of step with God’s character, it undermines justice, and it hurts people. That means lying directly contradicts the command to love our neighbor. Ultimately, lying isn’t a mouth issue. It’s a heart issue, and the only cure is a changed heart.
Lying Is Against God’s Character
God is completely truthful. He never lies, and his promises can always be trusted.
Hebrews 6:18 God did this so that, by two unchangeable things in which it is impossible for God to lie, we who have fled to take hold of the hope set before us may be greatly encouraged.
Because we’re made in God’s image, we’re called to reflect his truthfulness. Jesus described himself as “the way and the truth and the life” (John 14:6). Jesus called the devil “the father of lies” (John 8:44). When we lie, we’re acting more like the enemy than like our Father.
Lies Undermine Justice
The ninth commandment was originally about honest testimony in court. A false witness could ruin a person’s life. God gave Israel clear instructions.
Exodus 23:1 Do not spread false reports. Do not help a guilty person by being a malicious witness.
God cares deeply about justice. Gossip, slander, and spreading rumors are modern ways of giving false testimony. When we repeat things we don’t know to be true, we damage reputations and relationships.
Lies Hurt People
Lying isn’t just a violation of truth. It wounds people. Proverbs uses vivid images to make the point.
Proverbs 25:18 Like a club or a sword or a sharp arrow is one who gives false testimony against a neighbor.
Lies erode trust in marriages, friendships, workplaces, and churches. Even “little white lies” can chip away at relationships over time. Once trust is broken, it can take years to rebuild. That’s why Paul wrote, “Each of you must put off falsehood and speak truthfully to your neighbor” (Ephesians 4:25).
A Heart Issue
We often try to fix lying by watching our words more carefully. But Jesus said the problem goes deeper.
Matthew 15:18-19 But the things that come out of a person’s mouth come from the heart, and these defile them. For out of the heart come evil thoughts—murder, adultery, sexual immorality, theft, false testimony, slander.
Lying comes from a heart that wants to protect itself, impress others, or avoid consequences. The only lasting cure is a changed heart. Paul wrote, “Do not lie to each other, since you have taken off your old self with its practices and have put on the new self” (Colossians 3:9-10). Jesus gives us a new identity rooted in truth. As we grow, honesty becomes less about following a rule and more about reflecting who we really are in him.
The Takeaway
What is the ninth commandment all about? Lying is out of step with God’s character, undermines justice, and hurts people. It’s not just a mouth issue. It’s a heart issue, and Jesus offers the new heart we need to live in the truth.
