What does 2 Chronicles 15:9 mean?

He gathered everyone from Judah and Benjamin, along with people from Ephraim, Manasseh, and Simeon who had moved to Judah because they saw that the Lord was with Asa. 2 Chronicles 15:9 - Modern Text Bible

(People from other tribes joined Asa because they recognized that God was with him, showing how faithfulness can attract others.)