“The priests and the Levites, who were in all Israel, presented themselves to King Rehoboam from all their territories. The Levites had left their common lands and their holdings. They came to Judah and Jerusalem, because King Jeroboam and his sons had prevented them from serving as priests of Yahweh. He had appointed his own priests for the high places, and for the goat-demons, and for the calves which he had made. Those who had set their hearts to seek Yahweh God of Israel came after them from all the tribes of Israel to Jerusalem to sacrifice to Yahweh, the God of their ancestors. They strengthened the kingdom of Judah. For three years they made King Rehoboam the son of King Solomon secure. They walked for three years in the way of King David and King Solomon.”
There was no source for this material. This biblical author wanted to show how the northern priests and Levites left their towns and came to Jerusalem. According to Joshua, they should have stayed in their towns. For some reason, this wonderful exodus of priests, Levites, and good Yahweh believers lasted only 3 years. Something must have happened after 3 years. King Jeroboam of Israel had set up his own high places of worship. He even had his own priests with devil goats and god calves. There was no mention of his holy place at Bethel that was so contentious in 1 Kings, chapter 13. This also seems to ignore the false worship of King Solomon that led Yahweh to take away the northern territory from the current king of Judah.