God tells us in the Quran that as far as He is concerned the count of months is twelve (9:36) and that it has been that way since He created the Earth. He tells us that four of the twelve months are sacred and that we shall not wrong our souls by fighting during these Sacred Months.
The Sacred Months have been tampered with and alternated by those who do not truly follow the word of God, the Quran (9:37), the four Sacred Months are Zhul-Hijja, Muharram, Safar, and Rabi I (12th, 1st, 2nd, 3rd months of the lunar calendar).
Muharram ~ is the first month of the lunar calendar. It means ‘forbidden’. It is the second Sacred Month in which all fighting is forbidden.
Safar ~ the second month means ‘void/yellow/whistle’. It is a month known as ‘the whistling of the wind’ when the dry air blows through the sand dunes. It is the third Sacred Month when all fighting is prohibited.
Rabiul-Awwal ~ the third month of the calendar means ‘first month of spring’. It is the fourth Sacred Month in which fighting is not allowed.
Rabi-uthani ~ the fourth month means ‘second month of spring’, the month before the dry season begins in the desert.
Jumadi-ul-Awwal ~ the fifth month brings the first month of summer and means ‘first month of parched land’ when there is a lack of rain.
Jumadi-uthani ~ the sixth month which means ‘second month of parched land’.
Rajab ~ the seventh month of the calendar means ‘to respect’.
Sha'ban ~ the eighth month means ‘scattered’ when the tribes went in search of water.
Ramadan ~ the ninth month of is the month of fasting and it means ‘intense heat’. It is during this month that everyone who is able should fast from dawn until sunset.
Shawwal ~ the tenth month means ‘elevated’ when the female camels become pregnant and there is a shortage of camel milk.
Zhul-Q'ada ~ the eleventh month of the lunar calendar means ‘truce’.
Zhul-Hijja ~ the twelfth month meaning ‘pilgrimage’ is the beginning of the Hajj period when pilgrims make their way to Mecca to perform, possibly a once in a life time pilgrimage for God. It is the first Sacred Month which begins a cease to all fighting for four months.
The hajj/pilgrimage period is supposed to last for four months, but this too has been corrupted and reduced to one month of the year.
The Islamic calendar is based purely on the lunar cycle and it is not synchronised with the season of the year. It drifts each solar year by about eleven days and comes back into position with the solar cycle every thirty three years. The solar year has 365 days while the lunar year has 354 days.
The first year of the Hijrah calendar, used in countries like Saudi Arabia and Indonesia, was the year in which Mohamed emigrated from Mecca to Medina, known as the Hijrah. The corresponding Gregorian date is July 15th 622 AD.