דברי הימים ב, פרק כ״ה, פסוק כ״ה

The life of Amaziah, king of Judah, extended beyond the lifetime of Joash, king of Israel. A specific period of fifteen years is highlighted to mark the exact duration of this remaining time. This timeframe simply measures the additional years Amaziah continued to live after the passing of Joash [ביאור שטיינזלץ].