The lunar year is the year associated with the motion of the moon around the earth. The solar year is the year associated with the motion of the earth around the sun. In the Holy Qur’an, Allah has told us directly the duration of the lunar year. He did not tell explicitly the duration of the solar year, but instead gave us the exact mathematical formula that relates the solar year to the lunar year.
In Surah Taubah (9:36) Allah says
“The reckoning of months with Allah has been twelve months by Allah’s ordinance since the day when He created the heavens and the earth. Of these, four are sacred.”
These words determine that the lunar year has twelve months, because the lunar year is the one used by the Arabs, known as “Hijri year”, and it has four sacred months. The four sacred months in the Hijri year are, “Zulqe’da”, “Zulhejjah”, “Moharram” and “Rajab”. The solar year also has twelve months.
In the Arabic language (the Holy Qur’an language), there are two different words having the meaning of “year”. Those two words are the word “SANAH” and the word “AAM”. Almost all the Arabic speaking people are using both words indiscriminately.
In Surah Yunus (10:6) Allah says
“He it is Who made the sun radiate a brilliant light and the moon reflect a lustre, and ordained for it stages, that you might know the number of years (Sineen) and the reckoning of time..”
In this verse we see that the word “SINEEN”, which is the plural of the word “SANAH” is associated with the motion of the moon and its different stages. Therefore, the word “SANAH” means “LUNAR YEAR”.
Also in Surah Bani Isra’il (17:13) computation of years is mentioned . Allah says
“And We have made the night and the day two Signs, and the Sign of night We have made dark, and the Sign of day We have made sight giving, that you may seek bounty from your Lord, and that you may know the computation of years (sineen) and the science of reckoning. And everything We have explained with a detailed explanation.”
Al Kahf (18:20) Allah says about the people of the cave
“And so We raised them up that they might question one another. One of them said, ‘How long have you tarried?’ They said, ‘We have tarried a day or part of a day.’ Others said, ‘Your Lord knows best the time you have tarried”
“And they stayed in their Cave three hundred years (sineen), and added nine more.” Al Kahf (18:26)
After being asleep for three hundred and nine years, the cave people did not notice any change in the climate or the weather. Which means that the earth must have come to the same exact position in its orbit around the sun as it was 309 years ago. This implies that 309 lunar years are equal to 300 solar years.
Based on this mathematical relation, and since the solar year has 365.24 days, we find that the lunar year “Sanah” has 354.60 days, that is the lunar year is 10.64 days shorter than the solar year. Since the lunar year has twelve months we find that the lunar month has 29.55 days.
In Surah Ankabut 29:15, the two Arabic words for the word “year”, which are, “Sanah” and “Aam”, are mentioned. In this verse, Allah in His wisdom gave a rather noticeable expression, in order to let us know the difference between the two Arabic words, “Sanah” and “Aam”. Allah says
“And We certainly sent Noah to his people, and he dwelt among them a thousand years (sineen) save fifty years (Aam)…”
We have two different counts of the years. One count in terms of “Sanah” and another in terms of “Aam”. If the two words “Sanah” and “Aam” were the same, that is having the same duration of time, Allah would have said, nine hundred and fifty “Sanah” or nine hundred and fifty “Aam”. By this particular phrasing, Allah in His wisdom is giving us a pointer to think about the two words “Sanah” and “Aam”. This verse 29:15 is the only verse in the Holy Qur’an where the two words for a year “Sanah” and “Aam” were mentioned together to describe a period of time.
Using the mathematical relation shown earlier between the lunar year “Sanah” and the solar year “Aam”, we find that Prophet Noah’s dispensation lasted a period of 948.50 lunar years, which is equivalent to 920.87 solar years. Out of it, the first few decades (about ‘fifty years’) represent the years of spiritual progress, which are followed by many centuries (about 950 years ) of spiritual degeneration (29:15). The Quran not only doesn’t confirm Noah’s actual age, it doesn’t even mention it.Why should we discuss this at all? Is the actual age of Noah really important, or even relevant to us? If not, then what purpose would it serve in a handbook of divine enlightenment? it is inconceivable that the Quran, with its sole purpose to guide, would be concerned about any actual age.
Another example is in Surah Al-Baqarah (2:260) which depicts the story of a man who was passing by a village, which was completely in ruins. He wondered, how could Allah resurrect this village after its death. Allah then put him to death for one hundred years “Aam”, then resurrected him. In this verse, the Arabic word for a year “Aam” was used NOT the word “Sanah”. After his resurrection the man was then asked, “how long have you stayed ?”. The man said, “I have stayed a day or part of a day”. The man said that because when he was resurrected, he found that the weather conditions were the same as when he died. This indicates that after one hundred years “Aam”, the earth returned to the same position in its orbit around the sun as it was at the beginning of the hundred years “Aam”. This happens only, if those hundred years were solar years.
Allāhu ʾaʿlam [Allah knows best].
The hidden treasures of knowledge in The Holy Quran are for us to find. May Allah enable us to do so. Aameen.