What does 2 Kings 11:12 mean?

Then Jehoiada brought out Joash, put the crown on him, handed him the royal law, and anointed him king. Everyone clapped and shouted, 'Long live the king!' 2 Kings 11:12 - Modern Text Bible

(Joash is crowned and given the law, symbolizing both his authority and his responsibility to rule by God's standards. The people celebrate the return of a true king.)