History, Importance and Introduction to the Sacred Months
The Islamic calendar, also known as the Hijri calendar, is a lunar calendar consisting of 12 months in a year of 354 or 355 days. It is used by Muslims worldwide to determine the proper days for Islamic holidays and rituals, such as the annual period of fasting (Ramadan) and the time for Hajj pilgrimage.
The Arabs used a lunar calendar with intercalation (adding months) to synchronize with seasons. They recognized four sacred months where warfare was prohibited.
The Islamic calendar was established during the Caliphate of Umar ibn al-Khattab (RA), with the Hijra (migration) of Prophet Muhammad (ﷺ) from Mecca to Medina marking the beginning of the calendar.
Caliph Umar (RA) formalized the Hijri calendar as the official calendar of the Islamic state after consulting with the Prophet's companions.
The Hijri calendar remains the religious calendar for Muslims worldwide, while most Muslim-majority countries use the Gregorian calendar for civil purposes.
"Indeed, the number of months with Allah is twelve [lunar] months in the register of Allah [from] the day He created the heavens and the earth; of these, four are sacred." (Quran 9:36)
| Feature | Islamic Calendar | Gregorian Calendar |
|---|---|---|
| Type | Purely lunar | Solar |
| Year Length | 354-355 days | 365-366 days |
| Months | 12 (based on moon cycles) | 12 (fixed lengths) |
| Leap Years | 11 days shorter each year | Adds 1 day every 4 years |
| Starting Point | Hijra (622 CE) | Estimated birth of Jesus |
The Prophet (ﷺ) said: "The division of time has turned to its original form which was current when Allah created the heavens and the earth. The year is of twelve months, out of which four months are sacred: three are in succession Dhul-Qi'dah, Dhul-Hijjah and Muharram, and (the fourth is) Rajab..." (Bukhari)
Each month begins with the verified sighting of the new crescent moon. This traditional method follows the Prophetic practice but can lead to regional differences in start dates.
Some Muslim communities and countries use astronomical calculations to predict the new moon in advance, creating a predetermined calendar.
There is scholarly debate about whether to follow local sightings or accept sightings from anywhere in the world, leading to different practices among Muslim communities.