Matthew Poole and continuators on 2 Kings 17:15

15 And they rejected his statutes, and his covenant that he made with their fathers, and his testimonies which he testified against them, and they followed vanity , and became vain , and went after the heathen that were round about them, concerning whom the LORD had charged them, that they should not do like them.

i. e. Idols; oft so called, because of their nothingness, impotency, and unprofitableness; and to shew the folly and madness of Idolaters.

By the long worship of Idols, they were made like them, vain, sottish, and senseless Creatures.