What does Judges 3:7 mean?

The main body of the book of Judges begins with this verse. The writer has established all the reasons for what will happen in the stories to follow (Judges 1—2). Key details are that Israel disobeyed God by not removing all the wicked Canaanites from the Promised Land, so God will allow those remaining influences to harass Israel (Judges 2:20–23). In fact, this first verse is almost identical to the statement in Judges 2:11–13.

God's reasons for wanting to remove the Canaanites were moral, rather than racial or ethnic. Israel's evil, as condemned here, is directly tied to imitating the lifestyles of the local cultures (Deuteronomy 20:16–18). Israel not only failed to destroy these nations, but they even endorsed their culture by common marriages. They abandoned faithfulness to the Lord and served idols.

Worship of false gods is, of course, a grievous sin in and of itself. Deities associated with names like Ba'al, Asheroth, and Ashtaroth were fertility gods who promised wealth and abundance in return for worship. The worship of the Baals and the Asheroth, though, involved great evil on top of spiritual adultery against God. Worshipers of these gods participated in gross sexual immorality, debauchery, and even child sacrifices, in hopes of receiving blessings from these false deities.

Israel's fall into sin will result in oppression (Judges 3:8), and the rise of the first judge: Othniel (Judges 3:9).