New City Catechism 8.3
Question 8: What is the law of God stated in the Ten Commandments?
1. You shall have no other gods before me.
2. You shall not make for yourself an idol in the form of anything in heaven above or on the earth beneath or in the waters below—you shall not bow down to them or worship them.
3. You shall not misuse the name of the Lord your God.
4. Remember the Sabbath day by keeping it holy.
5. Honor your father and your mother.
6. You shall not murder.
7. You shall not commit adultery.
8. You shall not steal.
9. You shall not give false testimony.
10. You shall not covet.
The final commandment—“You shall not covet”—stands apart from the preceding commandments because it addresses the heart in a way that the others don’t. It is entirely possible that one could formally obey the command not to murder, not to commit adultery, not to steal, and not to give false testimony, all the while being consumed with sin in one’s heart through evil desire.
In our society today, the fundamental ethical principle seems to be that we can do whatever we want so long as we do no harm to others. Since coveting is a private matter that doesn’t affect my neighbor if I never act on it, what’s wrong with coveting? It doesn’t hurt anyone, right?
But if we begin with God as our reference point, the wickedness of coveting becomes clear. If I allow my heart to be consumed with desire for what I do not have, which often results in envy toward those who have it, what am I implicitly saying to God? I am saying to him that what he has chosen to give me is not good enough. I want more, and he is to blame for what I lack.
Coveting is the act that proceeds from a lack of gratitude to God. And a lack of gratitude is an indication that we do not rightly recognize God for who he is. And that is why coveting is not a harmless matter. It is deadly serious, as are all sins of the heart. The law of God addresses us here, at the point where we know we have all failed terribly. In doing so, the law points us to our only hope of redemption: the gospel of Jesus Christ.
Suggested passages for family or personal reading: Exodus 20:17; Romans 7:7-25. Why is coveting so bad? What does Paul teach about the relationship of sin to the law in Romans 7? How does the law point us to Christ?