– "Fa’adh-dhin": the imperative of adhān. What is meant here is to make a public announcement and inform the people that they are to fast the next day, since it is a day of Ramadan.
– "An yaṣūmū ghadan": the particle an is infinitive; the preposition and its object are omitted. The intended sense is: he proclaimed among them the fast of the coming day.

Points derived from the two ḥadiths

1. A single upright witness is sufficient to establish the beginning of Ramadan. The scholars say that this may even be a woman, for it falls under the heading of transmission; thus the fast of Ramadan becomes obligatory on the testimony of one person. Al-Tirmidhī said, “Most scholars act upon this.” It is the view of al-Shāfiʿī and Aḥmad. Al-Nawawī added, “This is the sounder opinion, for it is a religious report in which there is no room for suspicion, and it is safer for the act of worship.” As for the remaining months, the testimony of only one person is not enough; two upright men are required. Ibn ʿUmar and Ibn ʿAbbās said, “The Messenger of Allah ﷺ would accept no testimony for ending the fast except that of two men.” Al-Tirmidhī and others noted: the scholars are agreed that breaking the fast demands the testimony of two men, whereas one witness suffices for commencing the fast as a precaution for worship.
2. The witness must be legally accountable, meaning sane and past the age of puberty. Hence Ibn ʿUmar and the bedouin were both accountable when they testified to sighting the crescent.
3. The witness must be a Muslim of proven uprightness. The requirement of Islam is evident from the Prophet’s asking the bedouin whether he affirmed the two testimonies of faith, while uprightness is assumed for all the Companions.
4. Merely informing of the sighting fulfils the testimony; the formal wording “I testify…” is not required, just as in narrations and other reports.
5. Actively looking for the crescent is recommended, because important ritual rulings are contingent upon its sighting.