This question that was asked to the prophet (saws), by the Jews and polytheists at the time, about the moon phases was not actually an inquiry about the Islamic rules, rather they meant to put the Prophet (saws) in a critical situation. The Prophet (saws) was not an astronomer, but a guide, a bringer of good tiding, a warner and a caller to Allah (swt) as well, accordingly, he (saw) could only answer people at that time according to their mental ability of accepting information. Brains at that time were not able to comprehend the scientific facts about the earth, the space, the moon, the sun and the galaxies. Allah (swt) says:
{هُوَ الَّذِي جَعَلَ الشَّمْسَ ضِيَاءً وَالْقَمَرَ نُورًا }
(It is He who made the sun a shining light and the moon a derived light.) (Yunus: 5)
Until a time came when people revealed scientific facts, such as, the sun shines, because it is a self-illuminating source of light, whereas the moon lights by the reflection of sunlight on it, so when it is seen as crescents, this is according to sun light and has nothing to do with the moon light.
At that time, if the Prophet has wanted to explain to people the reality of the emergence of the crescent and how it begins as small and then grows and grows, their minds would have become confused; they won’t understand that the earth is spherical, and that the moonlight is as a reflection of the sun rays and its light. Therefore, the Holy Qur’an at first gives answers that direct people to the faith function which Allah (swt) wants from human. That is because the Holy Qur’an is a book of guidance and not a book of physics and astronomy. However, it is impossible for any verse or a word in the Holy Qur’an to contradict the science whatever it develops, and at any time, even after thousands of years. But, the scientific truths are hidden in the book of Allah (swt), so it gives the answers that give benefits to people. In this case what Allah (swt) answered this question?
(… قُلْ هِيَ مَوَاقِيتُ لِلنَّاسِ وَالْحَجِّ .. ) (..Say, “They are measurements of time for the people and for Hajj.”…): We measure the time of the month according to the moon, but the day is measured according to the sun, so the matter is related to time.
Hence, the moon phases or the appearance of the crescent in this shape is for the purpose of measuring the time, however, acts of worship are timely connected with the crescent. Likewise, Allah (swt) says:
{الْحَجُّ أَشْهُرٌ مَّعْلُومَاتٌ }
(Hajj is [during] well-known months,) (Al-Baqara: 197)
Merely, this act of worship is connected with the crescent, as in fasting:
{فَمَن شَهِدَ مِنكُمُ الشَّهْرَ فَلْيَصُمْهُ}
(So whoever sights [the new moon of] the month, let him fast it;) (Al-Baqara: 185)
You do not actually witness the month, but you fast when the month of Ramadan begins, how to know that? By timing which is known by seeing the crescent. From the scientific point of view, the Holy Qur’an refers to the spherical shape of the Earth, and points out that the sun is the source of the moon’s light.
The fact about the crescent is that the earth orbits, and the moon orbits too. Hence, while the earth moves around the Sun, it lies between the Sun and the Moon, so that it blocks the sunlight that is reflected on the moon, completely or partially. Accordingly, the crescent moon appears small and then becomes bigger gradually. The full shape of the moon means that the sun’s rays are fully projected on it and that the Earth is not in a position to block out any sunlight from the moon. In addition to other many scientific facts that the Holy Qur’an has stated, such as:
{وَالْأَرْضَ مَدَدْنَاهَا }
(And the earth – We have spread it.) (Al-Hujr:19)
which indicates that the shape of the earth is spherical. And Allah (swt) says:
{يُكَوِّرُ اللَّيْلَ عَلَى النَّهَارِ وَيُكَوِّرُ النَّهَارَ عَلَى اللَّيْلِ }
(He wraps the night over the day and wraps the day over the night.) (Az-Zumar: 5)
And Many other verses which indicate the spherical shape of the Earth.
However, the essential point is that the answer comes to serve a faith issue, similarly, when the Prophet (saws) was asked about the number of the companions of the cave:
{سَيَقُولُونَ ثَلَاثَةٌ رَّابِعُهُمْ كَلْبُهُمْ وَيَقُولُونَ خَمْسَةٌ سَادِسُهُمْ كَلْبُهُمْ رَجْمًا بِالْغَيْبِ ۖ وَيَقُولُونَ سَبْعَةٌ وَثَامِنُهُمْ كَلْبُهُمْ }
(They will say there were three, the fourth of them being their dog; and they will say there were five, the sixth of them being their dog – guessing at the unseen; and they will say there were seven, and the eighth of them was their dog.) (Al-Kahf: 22)
How does the Holy Qur’an answer this question? It mentions the important fact that benefits people, that is, they are young people who believed in their Lord. However, you get benefits from a lot of things without knowing how do they work. For example, you get benefits from the electricity without asking about its functionality.
What is important about this verse that the Prophet (saws) was asked about the crescent moon, whereas the answer came according to the interests of human beings; that is, it is a sign to mark fixed periods of time for mankind, same as the Hajj which also has a fixed place and time (Meeqaat), accordingly, you enter Makkah when you are in a situation of (Ihram).
(… وَلَيْسَ الْبِرُّ بِأَن تَأْتُوا الْبُيُوتَ مِن ظُهُورِهَا وَلَٰكِنَّ الْبِرَّ مَنِ اتَّقَىٰ ۗ وَأْتُوا الْبُيُوتَ مِنْ أَبْوَابِهَا ۚ وَاتَّقُوا اللَّهَ لَعَلَّكُمْ تُفْلِحُونَ ) (And it is not righteousness to enter houses from the back, but righteousness is [in] one who fears Allah. And enter houses from their doors. And fear Allah that you may succeed.…): In a previous verse:
{لَّيْسَ الْبِرَّ أَن تُوَلُّوا وُجُوهَكُمْ قِبَلَ الْمَشْرِقِ وَالْمَغْرِبِ }
(Righteousness is not that you turn your faces toward the east or the west,) (Al-Baqara: 177)
(… وَلَيْسَ الْبِرُّ بِأَن تَأْتُوا الْبُيُوتَ مِن ظُهُورِهَا ) (And it is not righteousness to enter houses from the back,.…): We would tell those who are skeptical of the Book of Allah (swt) from the orientalists and Ignorant: Only the qualified people in Arabic language and the Islamic science (Shari’a) can only interpret the Holy Qur’an, because it is in Arabic language:
{إِنَّا أَنزَلْنَاهُ قُرْآنًا عَرَبِيًّا لَّعَلَّكُمْ تَعْقِلُونَ }
(Indeed, We have sent it down as an Arabic Qur’an that you might understand.) (Yusuf :2)
Who does not know the Arabic language and its grammatical rules and the basics of its syntactic, certainly, he does not understand the Holy Qur’an, rather may have doubts about it.
Those who interpolated the verses, who wanted to use the Qur’an for their narrow and situational interests, they misinterpret the Book of Allah (swt) but they could not change any word of it because it is reserved by Allah (swt). There are people who accuse the Holy Qur’an and Islam of the injustice of women, and that Islam does not want freedom of human being, but Islam treats woman as honorable human being same as the man, however the Holy Qur’an has stated this fact in many verses, such as:
{يَا أَيُّهَا النَّاسُ إِنَّا خَلَقْنَاكُم مِّن ذَكَرٍ وَأُنثَىٰ وَجَعَلْنَاكُمْ شُعُوبًا وَقَبَائِلَ لِتَعَارَفُوا ۚ إِنَّ أَكْرَمَكُمْ عِندَ اللَّهِ أَتْقَاكُمْ ۚ إِنَّ اللَّهَ عَلِيمٌ خَبِيرٌ }
(O mankind, indeed We have created you from male and female and made you peoples and tribes that you may know one another. Indeed, the most noble of you in the sight of Allah is the most righteous of you. Indeed, Allah is Knowing and Acquainted.) (Al-Hujurat: 13)
{هُنَّ لِبَاسٌ لَّكُمْ وَأَنتُمْ لِبَاسٌ لَّهُنَّ }
(They are clothing for you and you are clothing for them.) (Al-Baqara: 187)
This integration and equality between women and men does not exist in any worldly law relate to women’s rights. However, the problem lies in the amputation of facts about our religion, and in our wrong understanding of the greatness of Islam.
Why did I mention the woman here? Because it was one of the traditions of the old Arabs that as soon as they return from the pilgrimage to the house of Allah (swt), after being absent for three or four months, they enter their houses from their top or back side to surprise the wife as if there is doubt about their wives’ chastity.
The Holy Qur’an aimed to break the incorrect concepts that prevailed, and put the concepts of chastity and trust between men and women, Allah (swt) says:
(… وَلَيْسَ الْبِرُّ .. ) (..And Righteousness is not that…): Righteousness means doing good deeds, therefore, it is not an act of faith, goodness neither a piety that is to have suspicions about your family. Doing so, the family will get upset when they feel that you are as if spying on them.
(… وَلَٰكِنَّ الْبِرَّ مَنِ اتَّقَىٰ .. ) (..but righteousness is [in] one who fears Allah…): Piety is a work of heart, not just acts and formalities. It is very important to achieve piety. Note the atmosphere of verses from the early ones about fasting until we reach this verse, piety is common in this chapter.
Because of the ignorance about the truth of our religion, the worshipping has been turned into only rituals and formalities; we do kneel, bow and apply the obligations without achieving the required goal. The purpose and the basis is the piety, that is because Allah (swt) has imposed these obligations and worship to promote the humans. All religions aimed at bringing benefits to human beings, to bring a mercy and not hardships. The verse which we always refer to in this regard is:
{وَمَا أَرْسَلْنَاكَ إِلَّا رَحْمَةً لِّلْعَالَمِينَ }
(And We have not sent you, [O Muhammad], except as a mercy to the worlds.) (Al-Anbiya’:107)
He (saws) was not sent as a misery, nor to bring terrorism, takfir or killing to humans. Mercy is the foundation and source of all good deeds, and the main purpose is to achieve piety.
(… وَاتَّقُوا اللَّهَ لَعَلَّكُمْ تُفْلِحُونَ ) (And fear Allah that you may succeed,.…): The origin of the Arabic word (Al-Falah) (success) is (Felaha) (agriculture). When you cultivate and plant a land, then you harvest it. The result of your hard work and fatigue is to obtain the fruits, this is the success, which is to achieve the goal, it is not the means and the method.
We are asked to fast, and fasting is achieved not only by refraining from food and drink but also refraining from disobedience and disputing, only then you will reach the goal which is the piety.