דברי הימים ב, פרק כ״ד, פסוק ב׳

The spiritual stability of King Joash was completely intertwined with the presence of his lifelong mentor. The king remained faithful to God, guided by the steady hand of Jehoiada the priest. Jehoiada was a man of high standing who enjoyed a long life and raised a large family, granting him a powerful and decisive influence over the ruler [ביאור שטיינזלץ].

However, the reality that this period of righteousness was limited to the lifetime of his mentor foreshadows the events that followed. The king's devotion to God lasted only as long as the priest was there to lead him. Following Jehoiada's death, an extreme reversal took place in the king's behavior. The officials of the kingdom approached Joash, bowed before him, and turned him into an actual object of idolatry, treating him as a god [רש״י].

The justification for this worship stemmed from the unique circumstances of the king's childhood. Because Joash had been hidden safely inside the Holy of Holies as a young boy and emerged completely unharmed, his officials claimed that he must possess divine qualities. They argued that surviving such an experience proved he was worthy of being worshipped as a deity [רש״י].