A transition of power in the Kingdom of Judah marks a significant historical milestone, intertwining the timelines of the newly divided kingdoms. The coronation of the new monarch, Abijam, serves as a bridge between the histories of Judah and Israel [ביאור שטיינזלץ].
The timing of this succession sparks a chronological discussion, as it occurs during the eighteenth year of King Jeroboam's reign in Israel. Since both Jeroboam and the previous king of Judah, Rehoboam, began their rule in the exact same year, the math requires some clarification. The primary approach among commentators is quite straightforward. They explain that Rehoboam ruled for seventeen full years before his death, making the following year, when his son assumed the throne, the eighteenth year of Jeroboam's reign. However, another perspective suggests that Rehoboam might have actually entered his eighteenth year but died before completing it, leading the year to be credited fully only to Jeroboam. Alternatively, an unexplained one-year delay might have occurred between Rehoboam's death and his son's official coronation [רד״ק].
The identity of the new king presents an interesting detail regarding his name. While he is known here as Abijam, other historical records refer to him as Abijah. This alteration was a practical choice made by the Israelites. Because King Jeroboam of Israel also had a son named Abijah, the people modified the Judean king's name to distinguish between the two. The slight change acted as a plural designation, essentially translating to "their Abijah" [מלבי״ם].
From the very beginning of his rule, the dark shadow of his father heavily looms over the new king. Abijam did not just inherit the throne, but he also inherited his father's corrupt nature and sinful behavior. He learned these ways directly, openly committing offenses even while his father was still alive [אלשיך]. Ultimately, this tragic choice to follow in his father's sinful footsteps sealed his fate. Because of his actions, his time on the throne was cut drastically short, lasting a mere three years [אברבנאל].