1 Kings 15:1

“Now in the eighteenth year of King Jeroboam the son of Nebat reigned Abijam over Judah.] That is, began to reign; and by this it appears that Rehoboam was in the eighteenth year of his reign when he died, for he and Jeroboam began their reign at the same time.”

“ABIJAM'S WICKED REIGN OVER JUDAH. (Kg1 15:1-8) Abijam--His name was at first Abijah (Ch2 12:16); "Jah," the name of God, according to an ancient fashion, being conjoined with it. But afterwards, when he was found "walking in all the sins of his father" [Kg1 15:3], that honorable addition was withdrawn, and his name in sacred history changed into Abijam [LIGHTFOOT].”

“Abijam reigned - So his reign began with Jeroboam's eighteenth year, continued his whole nineteenth year, and ended within his twentieth year, in which also Asa's reign began. And thus one and the same year may be attributed to two several persons. 3 Kings (1 Kings) 15:2”

“15:1-8 The author of 1 & 2 Kings describes the reign of each king of Judah in a typical pattern: the date of his accession in chronological relationship to the current king of the other kingdom (15:1), the length of his reign, the name of his mother (15:2), a spiritual evaluation of his character (15:3-5), details of his reign (15:6-7), sources where further data about him could be found (15:7), where he was buried, and his successor’s name (15:8). 15:1 Abijam (see study note on 2 Chr 13:1) reigned from 913 to 910 BC.”

“Kg1 14:31; Ch2 13:1, 2-22 3 Kings (1 Kings) 15:2”

“Reign of Abijam (cf., 2 Chron 13). - Abijam reigned three years, and his mother's name was Maacah, daughter (i.e., grand-daughter) of Absalom. We have the same in Ch2 11:20-21; but in Ch2 13:2 she is called Michajahu, daughter of Uriel of Gibeah. If אבישׁלום was without doubt Absalom, the well-known son of David, as we may infer from the fact that this name does not occur again in the Old Testament in connection with any other person, since Absalom had only one daughter, viz., Thamar ( Sa2 14:27), who was fifty years old when Solomon died, Maacah must have been a daughter of this Thamar, who had married Uriel of Gibeah, and therefore a grand-daughter of Absalom. This is sustained by Josephus…”