John Gill Commentary Psalms 106:36

"And served their idols, Which became a snare unto them." — Psalms 106:36 (ASV)

And they served their idols Of gold and silver, wood and stone; the works of men's hands, senseless creatures; which are nothing in the world, and bring grief and sorrow to the worshippers of them, from which they have their name here given them; see (Psalms 16:4) .

They served "their" idols, the idols of the Canaanites, who were dispossessed of their land for their idolatries and other sins; and these Israelites were put in their place. They served those which they were ordered to destroy; they who knew the true God, whose servants they were, or ought to have been, and professed to be, and were so called; and yet served the idols of the nations driven out before them.

Which were a snare to them; either the Canaanites were, who were left in the land, with whom they mixed, and whose works they learned; these ensnared them, and drew them into idolatry, (Joshua 23:13) , or the idols they worshipped, which were the cause of many evils and calamities, (Judges 2:3) , or the act of serving and worshipping them, (Exodus 23:33) (Deuteronomy 7:16) . They were by these means like a bird or beast in a snare, and brought into trouble and distress, out of which they could not extricate themselves.