Matthew Poole and continuators on 2 Kings 21:9

9 But they hearkened not: and Manasseh seduced them to do more evil than did the nations whom the LORD destroyed before the children of Israel .

Partly, because they were not contented with those Idols which the Canaanites worshipped, but either themselves invented, or they borrowed from other Nations many new Idols and kinds of Idolatry; and partly, because as their light was far more clear, their obligations to God infinitely higher, and their helps and antidotes against Idolatry much stronger than the Canaanites had; so their sins, though the same in kind, were unspeakably worse in respect of these dreadful aggravations.