1 Kings 15:34
And he did evil in the sight of the LORD, and walked in the way of Jeroboam, and in his sin wherewith he made Israel to sin. And he did evil in the sight of the LORD, and walked in the way of Jeroboam, and in his sin wherewith he made Israel to sin.
Baasha's course was one of unrepentant evil, doing what was evil in the sight of the Lord by walking in the way of Jeroboam and in his sin by which he made Israel to sin. That same refusal to repent was maintained after him by Elah, Zimri, and Omri, extending the evil course over a period of nearly forty years. It was a deliberate continuance of the idolatrous forms of worship introduced by Jeroboam, persisted in even after swift retribution had destroyed Nadab and all the house of Jeroboam.
From Jeroboam's death onward this course carried forward Israel's steady spiritual decline under rulers who did not fear Jehovah. Ruled by men who encouraged strange worship, the larger number of the people rapidly lost sight of the God of Israel. They became as idolatrous as the surrounding heathen.