Verse 17. - And Omri went up from Gibbethon ["The expression, 'went up,' accurately marks the ascent of the army from the Shephelah, where Gibbethon was situated, to the hill country of Israel, on the edge of which Tirzah stood" (Rawlinson)], and all Israel [see on ver. 16] with him, and they besieged Tirzah. [It is probable that they arrived before the city on the sixth or seventh day after the assassination of Elah. This period would just allow sufficient time for the news of the conspiracy to travel to Gibbethon and for the march of the army.]

16:15-28 When men forsake God, they will be left to plague one another. Proud aspiring men ruin one another. Omri struggled with Tibni some years. Though we do not always understand the rules by which God governs nations and individuals in his providence, we may learn useful lessons from the history before us. When tyrants succeed each other, and massacres, conspiracies, and civil wars, we may be sure the Lord has a controversy with the people for their sins; they are loudly called to repent and reform. Omri made himself infamous by his wickedness. Many wicked men have been men of might and renown; have built cities, and their names are found in history; but they have no name in the book of life.And Omri went up from Gibbethon, and all Israel with him,.... He, and the army under him, broke up the siege of that place, and marched to Tirzah; which, according, to Bunting (c) were thirty six miles distant from each other: and they besieged Tirzah; the royal city, in which Zimri was.

(c) Travels, &c. p. 162.