Nasai

Hadith Commentary:
The meaning is that sometimes the month consists of thirty days and sometimes of twenty-nine days.

Hadith Commentary:
(1)
Imam Bukhari rahimahullah has narrated this hadith with extreme brevity. In the narration of Muslim, there is detail: the Messenger of Allah sallallahu alayhi wa sallam indicated with the fingers of both hands and said that the month is like this, like this, and on the third time, he folded one finger and said, "like this," meaning 10+10+9=29, i.e., twenty-nine days; and sometimes it is like this, like this, and like this, meaning 10+10+10=30, i.e., a complete thirty days. (Sahih Muslim, Kitab al-Siyam, Hadith: 2511(1080))

(2)
The purpose of this hadith is to clarify that our acts of worship have been connected to open and clear signs. Therefore, in this scientific age, to extract the crescent moon using large telescopes and then, under the pretext of unity of the Ummah, to begin Ramadan or celebrate Eid on the same day in all Islamic countries is contrary to the nature of Islam. The Messenger of Allah sallallahu alayhi wa sallam, by indicating with his hands, pointed towards this natural simplicity.

(3)
Hafiz Ibn Hajar rahimahullah writes that by "calculation" is meant the calculation of astronomy, and the Arabs were unfamiliar with it. The Messenger of Allah sallallahu alayhi wa sallam made the commencement of fasting and the celebration of Eid dependent upon sighting the crescent so that the Ummah would not have to bear the hardship of calculation. This ruling will remain until the Day of Judgment, even if later there arise people who are experts in the science of astronomy.

(4)
The decision of the Messenger of Allah sallallahu alayhi wa sallam is that if, due to clouds or dust, the crescent is not sighted on the twenty-ninth day, then the current month should be counted as thirty days. He did not give any consideration whatsoever to calculation, otherwise he would have said, "Ask the people of calculation." The knowledge of the people of calculation is based merely on conjecture and estimation; it is not definitive. Therefore, if reliance is placed upon it, the matter becomes extremely dangerous. Furthermore, those who know the science of astronomy are very few. (Fath al-Bari: 163/4)

Benefits and Issues:
➊ (Ummah Ummiyyah) — One of the explanations of this phrase is that this (um) is attributed to "mother," and the meaning is such people who, in matters of knowledge and understanding, remain upon their maternal (innate) qualities, which we can describe as being devoid of knowledge. And in Arabia, the arts of teaching and learning came only through the blessing of Islam; before that, only a handful among them knew these disciplines. That is why it is translated as "unlettered" or "illiterate."

➋ Lunar months are sometimes twenty-nine days and sometimes thirty days. They are never twenty-eight or thirty-one days.

➌ In this narration of Abu Dawud, there is brevity. In other narrations, it is mentioned that on the second occasion, he (sallallahu alayhi wa sallam) gestured three times with the fingers of his hands. That is, sometimes the month is twenty-nine days and sometimes thirty days.

Therefore, an oath of a month is fulfilled in twenty-nine days. (What is the benefit of such repetition? See, Hadith: 2132)

Urdu marginal note:
Whether the month is of twenty-nine days or thirty, in any case it is considered complete, both in terms of rulings and in terms of reward.

“‘Unlettered people’—that is, we are acquainted only with innate knowledge, in which there is no possibility of error. We have not studied arithmetic, therefore we are not familiar with the sciences of mathematics, astronomy, or cosmology, etc. Nor is the reckoning of our months and years based on these sciences; rather, we determine the months by sighting the moon, which sometimes completes thirty days, and sometimes twenty-nine, and this is the true month. In contrast, the solar month is hypothetical; it has no apparent sign.”