لَمَّا قَلَّ الْمَاءُ فِي الْقَرْيَةِ، اجْتَمَعَ أَهْلُهَا عَلَى بَابِ الْمَجْلِسِ.
When water grew scarce in the village, its people gathered at the council door.
“Lammā” establishes a temporal setting for the subsequent action. Scarcity supplies the problem, gathering the communal response. “At the council door” identifies a location; the preposition itself does not establish honor, contempt or exclusivity.
The main effect is coherent narrative progression: occasion, public response and preparation for a speech. In an ordinary report, the clarity of plain declarative statements can be more fitting than added figurative ornament.