How Are Hijri Calendar & Hijra Related?
During the life of Prophet Muhammed (peace be on him) in Arabia, people distinguished years by the major events that occurred within them.
For example, the year when the Hijra took place—the migration of the Prophet and his Companions from Makkah to Madinah—was named ‘the year of the permission to travel’.
During Caliph Umar Ibn Al-Khattab’s fourth year, it became necessary to invent a calendar for precise timekeeping among the regions of the vast Islamic caliphate.
This stimulated much discussion about the establishment of an Islamic calendar to help distinguish between the years and standardize the dates of religious events.
The Companions discussed the numerous calendars used by others at the time, including the Persian, Egyptian and Jewish calendars.
Al-Hurmuzan, a prisoner of war following the Islamic conquest of Persia, suggested a Persian system known as mahruz, which was based on the victories of the Persian kings. Some Jewish converts to Islam suggested using the Hebrew calendar.
The Prophet’s Companions also contemplated whether the calendar should begin with the prophet’s birth, death or revelation. But they were unable to agree on the exact years of these events.
Eventually, 17 years after it happened, the Companions agreed that the Hijra would mark the beginning of the Islamic calendar, as there was no disagreement over the year in which it occurred.
According to some, such as Egyptian scholar and chronicler Abd al-Rahman al-Jabarti and Egyptian mathematician and astronomer Mahmud Pasha al-Falaki, the Prophet arrived at Quba Mosque in Medinah on the 8th of the third Hijri month, Rabi al-Awwal. On the 12th, he entered Medinah itself.
These dates were further discussed by some analysts of the prophetic biography, such as Al-Biruni, Ibn Sa’d, and Ibn Hisham, and cited in the works of Burnaby (2001).
Dates vary slightly between different scholars depending on their methods of calculation. Nevertheless, they all conclude that the Hijra took place during the end of the second Hijri month of Safar and the beginning of the third month of Rabi al-Awwal.
What about Muharram?
The Companions designated the first of Muharram as the first month in the Islamic calendar and the start of the Hijri year due to the numerous virtues associated with this month, such as the day of Ashura.
The Prophet has also described it as a great month of fasting, surpassed only by the month of Ramadan. Abu Hurairah narrated that the messenger of Allah (SAW) said:
“The most virtuous fasting after the month of Ramadan is Allah’s month Al-Muharram” (Jami` at-Tirmidhi 740).
‘Ubayd bin ‘Umayr, a son of a companion was quoted in ‘A History of Muslim Historiography’ of Franz Rosenthal as saying: “Al-Muharram is the month of God. It is the beginning of the year. It marks the beginning of the era. In al-Muharram, the Ka’bah is clothed, and money is coined. There is one day in al-Muharram on which repenting sinners are forgiven”.
Prehistoric humans used the changing shape of the moon to differentiate one month from the next. This enabled people to have some form of chronological order in their lives. They were able to understand the cycles of tides and to establish time patterns for rituals.
When ancient Egyptians began to engage in agriculture, they developed a solar calendar that accurately distinguishes between the weather cycles. It helped them establish precise times for crop harvests.
The Gregorian solar calendar eventually emerged as the most widely used calendar since the medieval ages.
Astronomically, there is a one-month difference between the lunar and solar calendars every four years. Hence, we add leap periods of time to realign the calendars with the weather and agricultural cycles.
Furthermore, the Qur’an mentions the moon in relation to timekeeping: “It is He who made the sun a shining light and the moon a derived light and determined for it phases – that you may know the number of years and account [of time]. Allah has not created this except in truth. He details the signs for a people who know” (Surat Yunus 10:5).
Allah also says: “Indeed, the number of months with Allah is twelve months in the register of Allah [from] the day He created the heavens and the earth; of these, four are sacred. That is the correct religion, so do not wrong yourselves during them. And fight against the disbelievers collectively as they fight against you collectively. And know that Allah is with the righteous [who fear Him]” (Surat At-Tawbah 9:36).
SOURCE: https://aboutislam.net/muslim-issues/science-muslim-issues/hijri-calendar-hijra-related/2/