דברי הימים ב, פרק י״א, פסוק ט״ז

The political split between Israel and Judah created a spiritual migration. Faithful followers of God from all the tribes refused to accept the new worship introduced by Jeroboam in the north, preferring to uproot themselves to preserve the original worship of God. Following the migration of the priests and Levites to the south, additional people from all the tribes of Israel were drawn to Jerusalem [רש״י, מצודת דוד, ביאור שטיינזלץ]. Out of deep faith, these individuals continued to view themselves as deeply connected to the Temple in Jerusalem and its daily service [ביאור שטיינזלץ].

This migration had broad political consequences. The steady influx of arrivals seeking to sacrifice to God significantly strengthened the small kingdom of Judah, transforming it into a powerful and populous nation. Ironically, Jeroboam's plan to secure his rule by making golden calves and dismissing the priests of God from their duties worked against him. The strategy became a trap, as it specifically strengthened the dynasty of David and emboldened Rehoboam against Jeroboam.

This positive trend continued throughout the first three years of Rehoboam's reign, during which the people followed the path of David. Eventually, however, they too acted unfaithfully, which ultimately brought about the weakening of the kingdom [מלבי״ם].