1 Kings 12:31
And he made an house of high places, and made priests of the lowest of the people, which were not of the sons of Levi. And he made an house of high places, and made priests of the lowest of the people, which were not of the sons of Levi.
Jeroboam built houses for worship on high places at Bethel and Dan as a rival system set up in opposition to the worship of God at the temple in Jerusalem. When he could not persuade the Levites living in his territory to serve in those shrines, he made priests from the lowest of the people, men who were not of the sons of Levi. Many faithful people, including Levites, left his territory and fled to Jerusalem so they could worship according to God's requirements.
His course in making this false priesthood and sanctuary sprang from selfishness and rebellion. His plans led Israel away from God and away from true worship into idolatry and into performing and permitting terrible evils. His attempt to make the dedication of the strange altar solemn and impressive could not make that worship right. The prophet's message against this worship should have led him to repent and abandon his wicked purposes, but he hardened his heart and chose his own way.
Men today are in danger of manifesting the same spirit of selfish rebellion and of doing a work similar in character to the work he did. The Judge of all the earth lays the awful results of his course to his charge, and to the charge of those who follow his example will be laid the results of their own wrong course.