Albert Barnes Commentary Judges 6:10

"and I said unto you, I am Jehovah your God; ye shall not fear the gods of the Amorites, in whose land ye dwell. But ye have not hearkened unto my voice." — Judges 6:10 (ASV)

A similar use of the name Amorite, instead of the more usual name Canaanite, occurs in Joshua 24:15, 24:18. Perhaps a special reason may be found for using the name Amorite if the prophet was addressing those who lived in the mountains, where the Amorites primarily lived. The idolatries of the Amorites seem, too, to have been especially abominable (see 2 Kings 21:11; 1 Kings 21:26).

It should be observed that as the prophet’s language traces Israel's misery to their sins, it also suggests the necessity of repentance and of forsaking their sins—especially the sin of idolatry—before any deliverance. In exact accordance with this view, Gideon begins his work by throwing down the altar of Baal and building up the altar of Yahweh (Judges 6:24–25).