In the Name of God, Most Gracious, Most Merciful

Fasting and the Islamic Calendar

The Islamic Calendar, is as old as Islam (Submission). It dates back to the oldest known civilization. God in the Quran tells us that, our religion, Islam (Submission in English), is the oldest and same religion known to mankind. All God's prophets and messengers came with the same message of submission (Islam), to submit to the One and only God.

[3:19] The only religion approved by God is 'Submission' (Islam in Arabic), those who received the scripture are the ones who dispute this fact, despite the knowledge they have received, due to jealousy. For such rejecters of God's revelation, God is most strict in reckoning.

Adam, the first submitter, being the first human being, was ordered to submit to the One and only God, and when he sinned, the Most Merciful gave him the key for repentance. Reviewing the history of calendars show that when God created the universe, He created the Lunar and Solar calendar.

[9:36] The count of months, as far as God is concerned, is twelve. This has been God's law since the day He created the heavens and the earth. Four of them are sacred.....

The first chapter of the Bible, "the Story of Creation" states, "Let there be lights in the firmament of the heaven to divide the day from the night; and let them be for signs, and for seasons, and for days, and for years." (Genesis i. 14)

God used the word "Month" 12 times throughout the whole Quran and the word "Day" 365 times throughout the whole Quran. The relationship here to the solar year is not a coincidence. In Chapter (Sura) 18, in the story of the people of the cave (the Seven Sleepers of Ephesus), God informs us that they stayed in their cave three hundred years, increased by nine (18:25). It turns out to be that three hundred solar years are equal to 309 lunar years, thus emphasizing the direct link between the solar and lunar calendars.

The calculation for the Lunar year is emphasized in the Quran.

[10:5] He is the One who rendered the sun radiant, and the moon a light, and He designed its phases that you may learn to count the years and to calculate. GOD did not create all this, except for a specific purpose. He explains the revelations for people who know.

The calculation for the Solar year is emphasized in the following verse.

[17:12] We rendered the night and the day two signs. We made the night dark, and the day lighted, that you may seek provisions from your Lord therein. This also establishes for you a timing system, and the means of calculation. We thus explain everything in detail.

The day and night are the result of the movement of the sun as we know.


Historians have been talking about the calendars as a creation of man, completely ignoring the reasons behind the perfect system in the sky that enabled man to mark his days, weeks, months and years. They missed the fact that the calendars are a deliberate design of the One and Only Creator, God Almighty, the Most Gracious, the Omniscient, the Cognizant.

Throughout the existence of mankind, people have been aware of the special rhythms of the sun and the moon. The rudiments of a calendar system may have been constructed as long ago as 2000 BC, when stone alignments were used, it is believed, to determine the length of the solar year by marking the progress of the Sun along the horizon. Centuries after the Quran came with the notion that the sun and the moon are moving in a measurable orbit , did the astronomer Nicolas Copernicus (1473-1543) came up with the idea that , the sun stood still, and the earth was one of a group of heavenly bodies moving around it, and that as the earth moved in a measurable orbit around the sun and the moon traveled around the earth in its own measurable path. See Quran, 55:5, 36:38-39, 10:5, 31:29 and 39:5.

Centuries before the Quran, Meton of Athens (5th century BC) calculated the 19-year "Metonic cycle." Meton calculated that 19 solar years corresponded to a lunar cycle. The calculation of the birth of a new moon has been available to us humans since that time.


The ancient Sumerians devised the first known lunar calendar about 5,000 years ago. The Moon's phases occur over an easily observed interval, the month. Religious authorities declared a month to have begun when they first saw the new crescent Moon. During cloudy weather, when it was impossible to see the Moon, the beginning of the month was determined by calculation.

The interval from new moon to new moon, called a synodic month, is about 29.53 days. Hence, calendar months contained either 29 or 30 days. Twelve lunar months, which total 354.36 days, form a lunar year, almost 11 days shorter than a typical (solar) year.

Later Babylonians divided months into weeks and a week into 7 days. The Jews, once captive in Babylonia, used the Babylonian 7-day week, as did the sun-worshipping Egyptians, who developed a 52 week solar calendar based on the 7-day week.

A lunar year is not suitable for agricultural purposes. To keep in step with the Sun, lunar-solar calendars were formed by adding an additional (leap) month when the observation of crops made it seem necessary. Hundreds of such calendars, with variations, were formed at various times in such different areas as Mesopotamia, Greece, Rome, India, and China.

Romans, during the late republic, used various lunar-solar calendars. These calendars were supposedly based only on observation, but in fact they were influenced by political considerations. The Roman calendar was in error by several months during the reign of Julius Caesar, who recognized the need for a stable, predictable calendar and formed one with the help of an astronomer, Sosigenes. The year 46 BC was given 445 days, to compensate for past errors, and every common year thereafter was to have 365 days. Every fourth year, starting with 45 BC, was to be designated a leap year of 366 days, during which February, which commonly had 28 days, was extended by one day. The rule was not correctly applied, but the calendar was corrected by Augustus Caesar by AD 8.


The Julian leap-year rule created 3 leap years too many in every period of 385 years. As a result, the actual occurrence of the equinoxes and solstices drifted away from their assigned calendar dates. As the date of the spring equinox determines that of Easter, the church was concerned, and Pope Gregory XIII introduced what is now called the Gregorian calendar. Wednesday, Oct. 4, 1582 (Julian), was followed by Thursday, Oct. 15, 1582 (Gregorian); leap years occur in years exactly divisible by four, except that years ending in 00 must be divisible by 400 to be leap years. Thus, 1600, 1984, and 2000 are leap years, but 1800 and 1900 are not.

The Gregorian civil calendar is a solar calendar, calculated without reference to the Moon. However, the Gregorian calendar also includes rules for determining the date of Easter and other religious holidays, which are based on both the Sun and the Moon. The Gregorian calendar was quickly adopted by Roman Catholic countries. Other countries adopted it later, sometimes choosing only the civil part. It was not adopted by the Soviet Union until 1918; Turkey did not adopt it until 1927.


The year used to begin at different times in different localities. The Roman year began in March. December, whose name is derived from the Latin word for "ten," was the tenth month of the year. In 153 BC, Roman consuls began taking office on January 1, which became the beginning of the year. This practice was retained in the Julian and Gregorian calendars, although other starting dates continued to be used; England and its colonies, for example, used March 25 and the Julian reckoning until 1752. Thus, George Washington was officially born on Feb. 11, 1731, Old Style (O.S.); this is Feb. 22, 1732, Gregorian, or New Style (N.S.).


The Babylonians used a non astronomical, 7-day interval, the week, which was adopted by the Jews. The seventh day, the Sabbath, was given a religious significance. Independently, the Romans associated a cycle of 7 days with the Sun, the Moon, and the five known planets. Their names became attached to the days of the week: Sunday (dies solis, "Sun's day"), Monday (dies lunae, "Moon's day"), and Saturday (dies Saturni, "Saturn's day") retain their names derived directly from the Roman culture, and Tuesday ("Tiw's day"), Wednesday ("Woden's day"), Thursday ("Thor's day"), and Friday ("Frigg's day") are derived from the Germanic equivalents of Mars, Mercury, Jupiter, and Venus, respectively.


In ancient calendars, years were generally numbered according to the year of a ruler's reign. About AD 525, a monk named Dionysius Exiguus suggested that years be counted from the birth of Christ, which was designated AD (anno Domini, "the year of the Lord") 1. This proposal came to be adopted throughout Christendom during the next 500 years.

The year before AD 1 is designated 1 BC (before Christ). Dionysius had referred the year of Christ's birth to other eras. Modern chronology, however, places the event at about 4 BC. The 1st century of the Christian Era began in AD 1, the 2d in AD 101; the 21st will begin in 2001.


The Hebrew calendar in use today begins at the Creation, which the Jewish scholars calculated to have occurred 3,760 years before the Christian era. The week consists of 7 days, beginning with Saturday, the Sabbath; the year consists of 12 lunar months--Tishri, Heshvan, Kislav, Tebet, Shebat, Adar, Nisan, Iyar, Sivan, Tammuz, Ab, and Elul--which are alternately 29 and 30 days long. Because a year is some 11 days longer than 12 lunar months, a 13th month ve-Adar, is added seven times during every 19-year cycle


The Islamic Calendar began at the day and year (July 16, 622, by the Gregorian calendar) when the Prophet Muhammad emigrated from Mecca to Medina. There are 12 lunar months of alternate 30 and 29 days, making the year 354 days long. The months are Muharram, Safar, Rabi I, Rabi II, Jumada I, Jumada II, Rajab, Shaban, Ramadan, Shawwal, Zulkadah, and Zulhijjah.

The Islamic calendar divides times into cycles 30 years long. During each cycle, 19 years have the regular 354 days, and 11 years have an extra day each. Notice that number 19 is mentioned in verse 30 in the Quran in Sura 74 (7+4=11), so 19, 30, 74 (7+4= 11) are all there in the solar system designed by the same God who put number 19 in verse 30 of sura 74. It is also interesting to know that the sun, the moon and the earth all align in the same relative position once every 19 years.

The Islamic day as we can now appreciate is the same day used by the oldest civilization, the same as the Hebrew day. It begins at sunset and ends at the next sunset. In the Story of Creation, in the Bible, it says :

"And there was evening and there was morning one day."

Evening marked the beginning of the new day.

In Quran, God always mentions the night before the day.

[21:33] And He is the One who created the night and the day, and the sun and the moon; each floating in its own orbit.

When God ordered us to fast Ramadan, He ordered us to eat and drink first until dawn then fast to the night. A great sign that Ramadan (and every lunar month) starts at night (sunset) and ends at night.

[2:187] ........... You may eat and drink until the white thread of light becomes distinguishable from the dark thread of night at dawn. Then, you shall fast until sunset. ..........


To calculate when a new lunar month begins we need to know two facts, the first is the exact time of the birth of the new moon, and the second fact is the exact time of the sunset of the same day. The new lunar month begins theoretically at the birth of the new moon, but begins practically at the first sunset to follow the birth of the new moon. God already gave us enough knowledge to calculate the beginning of the first day of Ramadan for the next hundreds of years. Sighting of the moon, to determine the new Islamic month, is an invention by the scholars that they took after the Jewish Rabbis who insist on sighting of the moon for their Jewish Lunar months. Sighting of the moon is not in the Quran, but was a way of recognizing the beginning of the lunar month for those who lived in the desert and have no other means to recognize the beginning of the new month. God in the Quran reminds us that the phases of the moon are only a tool to calculate the calendar and the time for pilgrimage (Hajj), see 2:189. God never said in the Quran that sighting of the crescent moon is a requirement to determine the beginning of the new lunar month.

God is all Omniscient, Knower of everything, He knows that different generations will have different means of calculating the time of the birth of the new moon. Now, with all the knowledge we have, we cannot sit still knowing that the month has already started and wait for a scholar to go look for the crescent moon that may or may not be visible because of many factors, the most common of them is the weather condition. The believers believe God in His own book and realize that God meant it when He said that His book, the Quran, is complete, perfect and fully detailed. And that it has the details and explanations of everything we need for our salvation.

[16:89] The day will come when we will raise from every community a witness from among them, and bring you as the witness of these people. We have revealed to you this book to provide EXPLANATIONS FOR EVERYTHING, and guidance, and mercy and good news for the submitters.

[12:111] In their history, there is a lesson for those who possess intelligence. This is not fabricated Hadith; this (Quran) confirms all previous scriptures, provides the DETAILS of EVERYTHING, and is a beacon and mercy for those who BELIEVE.


  1. The Glorious Quran
  2. Mathematical Miracle of the Quran, Appendix 1 of authorized English Translation of Quran by Rashad Khalifa,Ph.D.
  3. The Bible
  4. Grolier Electronic Publishing, Encyclopedia:

    Archer, Peter, The Christian Calendar and the Gregorian Reform (1941); Asimov, Isaac, The Clock We Live On(1963); Keane, Jerryl, Book of Calendars (1981); Michels, A.K., The Calendar of the Roman Republic (1967; repr. 1978); Monaco, James, The French Revolutionary Perpetual Calendar (1982); Philips, Alexander, The Calendar: Its History, Structure, and Improvement (1921); Schocken, W. A., Watkins, Harold, Time Counts: The Story of the Calendar (1954).