Then Omri and all the Israelites marched up from Gibbethon and besieged Tirzah.
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
But the people that followed Omri prevailed against the people that followed Tibni the son of Ginath,.... Very probably they had a battle, in which the latter were worsted: so Tibni died; in the battle: and Omri reigned; took possession of the throne, his rival being slain.
And Omri went up from Gibbethon, and all Israel with him, and they besieged Tirzah. (h) Where Zimri holed up.