The reference to Israel’s forgetting the Lord does not mean they suffered amnesia. No doubt they still remembered the Midianite victory. Rather, the issue at hand was their failure to take into account Yahweh’s past saving acts on their behalf and to respond in accordance with his gracious salvation. How true this was will be demonstrated in the following chapter, which exhibits no knowledge of or allegiance to Yahweh whatsoever.
1
34 And the people of Israel did not remember the LORD their God, who had delivered them from the hand of all their enemies on every side,