vision of the crescent moon. Learn Islam for converts and beginners for free. Information about the Muslim religion. Sunni Muslim website. Islam.ms.
The beginning of the month of Ramadan, as well as the end of the month, is determined by sighting the crescent. If the crescent was not sighted, then the month would be completed by thirty days, as is the case with determining all the months of the lunar calendar. This is taken from the Hadîth of the Prophet صلى الله عليه وسلّم related by Al-Bukhâriyy and Muslim: « لا تَقَدَّمُوا رَمَضانَ بِيَومٍ أَوْ يَومَين صُوموا لرؤيتِه وأفطِرُوا لرُؤيتِه فإنْ غُمَّ علَيكم فأكْمِلوا عِدَّةَ شَعبانَ ثلاثينَ يوما », which means: « Do not fast one or two days before Ramaḍān. Start the month when you see the crescent, and end it when you see the crescent. If you are blocked from seeing it, then complete thirty days of Sha`bân. »
The Aḍ-ḥā `Id is one of the great days of the year on which the pilgrim fulfils the obligations of Hajj. It is also recommended for the pilgrim to offer a sacrifice on that day, with the intention to gain rewards from Allâh, the Exalted. This act is a regularly practised sunnah by the Prophet. Hence, the pilgrim and the non-pilgrim can practise this sunnah. This is evidenced in the ayah: فَصَلِّ لِرَبِّكَ وَانْحَرْ the meaning of which is: « Perform the `Id Prayer and offer a sacrifice seeking reward from Allâh. »