Charles Ellicott Commentary 2 Kings 21:22

"and he forsook Jehovah, the God of his fathers, and walked not in the way of Jehovah." — 2 Kings 21:22 (ASV)

And he forsook the Lord ... —And he forsook Jehovah, the God of his fathers; he abandoned His worship altogether and gave himself up to foreign superstitions which his father had introduced. It is noteworthy that the long reign of Manasseh-Amon is described by the sacred historian simply in terms of its relation to the religion of Israel.

The astonishing corruption of worship that broke out during this period; the perverted longing for foreign rites, which appears to have been only intensified by the restraints endured under Hezekiah; the bloody persecution of those who maintained the ancient faith; the prophetic menaces of coming retribution—these are the main points of the brief but impressive story. As usual, moral and religious license went hand in hand. The prophet Zephaniah denounces all the ruling classes of the rebellious and polluted city; princes and judges, prophets and priests, are involved in the same condemnation (Zephaniah 1:4–5; Zephaniah 3:1–4; compare Micah 6:10 and following, Micah 7:2–6).