When Zimri saw that the city was captured, he entered the citadel of the royal palace and burned it down upon himself. So he died
Solomon observes (Pro 28:2) that for the transgression of a land many were the princes thereof (so it was here in Israel), but by a man of understanding the state thereof shall be prolonged - so it was with Judah at the same time under Asa. When men forsake God they are out of the way of rest and establishment.
Commenting on 1 Kings 16:15-28
In the thirty first year of Asa king of Judah began Omri to reign over Israel twelve years,.... Which are to be reckoned not from the thirty first of Asa; for Ahab the son of Omri began to reign in his thirty eighth year, and so his reign would be but seven or eight years; but they are reckoned from the twenty seventh of Asa...
1Ki 16:15-18 The Reign of Zimri lasted only seven days. As soon as the people of war (העם), who were besieging Gibbethon (see at 1Ki 15:27), heard of his conspiracy, his usurpation of the throne, and his murderous deeds, they proclaimed Omri king in the camp of the military commanders, and he at once, with all Israel, i.e., all the army, raised the siege of...
Commenting on 1 Kings 16:15-18