c-1 The Years King Asa Reigned
1 Kings 16:6-8 says Elah, the son of king Baasha of Israel, was king after Baasha’s death in the 26th year of king Asa’s reign in Judah. Now 2 Chron.16:1 says Baasha attacked Judah in the 36th year of Asa's reign, long after Baasha’s death indicated in 1 Kings. Chronicles amplifies Kings to show that there is no textual error here.
As others note, the 36 years can be the time since the divided kingdom began with Rehoboam, who ruled Judah 17 years, followed by Abijam who ruled 3 years. If this 20-year period prior to Asa’s rule is subtracted from the 36 years, Baasha’s attack of Judah would be in the 16th year of Asa, which fits well chronologically.
The prior 20 years of a divided kingdom are assigned to Asa in 2 Chronicles 16:1. Rehoboam and Abijam represented Judah poorly, lacking wisdom and not doing God’s will (1 Kings 12:1-24, 15:3,4). Judah had separated from other tribes, and was to be a new Israel obedient to God. Asa, the first good king of Judah in the divided king- dom, usually followed God. His reign, not those of the prior two kings, would properly represent a new Israel. Thus a true Judah rightly begins with Asa, and the prior 20 years are added to his reign to recognize, figuratively, a literal disenfranchising of the two disobedient kings, and the literal beginning of the kingdom with Rehoboam.