Religious Affairs Office

The Islamic calendar follows the lunar cycle, in which months begin and end with a new moon, just as days begin and end with sunset. In the case of two stars with different orbits, the lunar months do not always coincide with the solar months, which is why a retroactive lag of about ten days per year occurs. That is, the lunar months rotate through all the seasons in a cycle of approximately 36 years.

In pre-Islamic times, the duration of the calendar was not fixed, Islam established it by prohibiting the practice of occasionally intercalating months or days to adjust or extend (nasâ') the lunar calendar to the solar calendar (Quran, IX, 36 and 37): the only criterion accepted when establishing the calculation is the strictly lunar one, as can be seen in the setting of the month of Ramadan (Quran, II, 185).

The beginning of the Islamic calendar is established in the year 638 of the Gregorian calendar, at the time of Caliph 'Umar b. al-Ḫattâb, and from a key episode in the history of Islam: the exile (hijra or hegira) of the Muslims to the city of Medina in the year 622. Although the Islamic community had already suffered other minor exiles to African lands, the exile to Medina is the one that is considered the most important and decisive.

The Islamic calendar has twelve months, of which four are considered inviolable: muḥarram, rajab, ḏû-l-qa'da and ḏû-l-ḥijja. The Arabic word used to distinguish these months is harâm, a concept that could be translated as "inviolable" or "carrying limitations, prescriptions or prohibitions", with reference to the pre-Islamic periods of pilgrimage and truce. Islam echoed and accepted them.

The Islamic lunar year has between 354 and 355 days, divided into months of 29 or 30 days (yawm). The days are grouped into weeks (usbû') and take their name from their numerical order: Sunday is the first day (yawm al-ahad) and Saturday is the seventh and last (yawm as-sabt). The exception is Friday (yawm al-juma'), which takes its name from the midday prayer, when the entire community (jamâ‘) tries to gather.

Islam only recognizes two festivities: the "small festivity" of breaking the fast ('îd al-fiṭr) which marks the end of Ramadan (first day of the month of šawwâl) and the "great festivity" of sacrifice ('îd al -aḍḥa) marking the end of the annual pilgrimage to Mecca (tenth day of ḏû-l-ḥijja). If the Judeo-Christian tradition emphasized the liberating and "sabbatical" sense of the festivity, Islam adds the sense of cyclical regeneration (i'âda), as expressed, for example, in the prophetic tradition (sunna) of going to and returning from the festivity prayer by different ways.