“They took the Canaanites’ daughters as wives and gave their daughters to the Canaanites; they worshiped their gods as well.”
The people of Israel did not fully obey the Lord and clear the land of Canaan of the pagans. As a result they intermarried and worshiped their gods.
The Christian’s goal is to be fully devoted to God. All entanglements that prevent this are avoided. What does it mean to be unequally yoked? 2 Cor 6.14.