Albert Barnes Commentary 1 Kings 12:27

"if this people go up to offer sacrifices in the house of Jehovah at Jerusalem, then will the heart of this people turn again unto their lord, even unto Rehoboam king of Judah; and they will kill me, and return to Rehoboam king of Judah." — 1 Kings 12:27 (ASV)

Kill me — If his subjects desired a reconciliation with Rehoboam, Jeroboam’s death would at once facilitate the re-establishment of a single kingdom and win favor with the legitimate monarch (Compare 2 Samuel 4:7).