Is the sighting of the new moon in one locality binding for all other localities regarding the commencement of fasting?
General Chapter
Al-Mughni
Book of Fasting
Primary text
If the inhabitants of one city sight the new moon, fasting becomes obligatory for all lands. This is the view held by Al-Layth and some scholars from the Shafi'i school. The evidence for the general obligation is derived from the verse, "So whoever among you witnesses [the month, i.e., residency at home] of the month, let him fast it" (Quran 2:185), and the Prophet's confirmation to the Bedouin that God commanded him to fast that month, affirming the obligation based on witnessing the month. Furthermore, Muslims have reached consensus on the obligation of fasting the month of Ramadan, and when trustworthy witnesses confirm a specific day is part of Ramadan, fasting becomes incumbent upon all Muslims. The month of Ramadan is established between the two moon sightings, and establishing a day as belonging to it affects all rulings, such as debt maturity, divorce, manumission, and vows, thus requiring fast based on text and consensus. Additionally, if a just and reliable witness testifies to sighting the moon, fasting is obligatory, just as it is when locations are geographically close.
Supporting text
A dissenting view states that if the distance between two cities is small enough that their lunar horizons do not significantly differ, such as Baghdad and Basra, fasting becomes obligatory for both based on the sighting in one. However, if the distance is great, such as between Iraq, Hijaz, and Sham, then each region must rely on its own sighting. This view is supported by 'Ikrimah, Al-Qasim, Salim, and Ishaq, based on the report of Kurayb, who experienced a difference in sighting dates between Sham and Medina, where Ibn Abbas preferred Medina's sighting based on following the Prophet's directive concerning communal practice.