From a comparison of the dates given in 1 Kings 16:15, 1 Kings 16:23, 1 Kings 16:29 it follows that the contest between the two pretenders lasted four years.
Tibni’s death can scarcely be supposed to have been natural. Either he must have been slain in battle against Omri, or have fallen into his hands and been put to death.
There has probably been some derangement of the text here. The passage may have run thus: “So Tibni died, and Omri reigned in the thirty-first year of Asa, king of Judah. Omri reigned over Israel twelve years: six years reigned he in Tirzah.” Omri’s reign of 12 years began in Asa’s 27th 1 Kings 16:15-16, and terminated in his 38th 1 Kings 16:29. The event belonging to Asa’s 31st year was the death of Tibni, and the consequent extension of Omri’s kingdom.
The six years in Tirzah are probably made up of the four years of contention with Tibni, and two years afterward, during which enough of Samaria was built for the king to transfer his residence there.