Calculated Moon Sightings

It has become an unfortunate issue that there is so much debate every Ramadan around the citing of the moon. I have always felt it best to refrain from the debate, acknowledge the difference of opinion and follow your local community which you trust.

I recently came across a post by one of my former teachers Ustadh Mohammad Jamili, may Allah bless and preserve him. It demonstrates a legitimate difference of opinion which exists within the Shafii school, one of the universally recognised schools of Islamic law. Such difference often results from a different understanding of the texts or contexts, and has always been understood to be a mercy for this nation.

As we lack a central authority in the West to set the universal holidays for us, its is important to recognise such difference as legitimate and allow individuals to follow the authority they trust.

And Allah knows best!


The Shafi school regarding astronomical calculations has two opinions and both are sound and reliable in the school.

The first is that of Ibn Hajar Al-Haytami who says in Tuhfat Ul-Muhtaj

“لا قول منجم و هو من يعتمد النجم ، و حاسب و هو من يعتمد منازل القمر و تقدير سيره، و لا يجوز لأحد تقليدهما. نعم لهما العمل بعلمهما و لكن لا يجزئهما عن رمضان كما صححه في المجموع و إن أطال جمع في رده”

“Ramadhan is not established by the munajjim, who uses the stars to calculate the month, nor by a haasib, who uses the moon cycles for this. It is not permissible to follow either of them two. It is allowed for them to act upon their own findings but it will not be sufficient for them to establish Ramadhan.”

The second is that of Imam Ramli, Khatib and some others. Imam ash-Sharwani on his commentary on Tuhfah said,

“ذكر شيخنا الشهاب الرملي و وافقه الطبلاوي الكبير على الوجوب و الإجزاء قال م ر و لهما العمل بالحساب و التنجيم أيضا في الفطر آخر الشهر إذ المعتمد أن لهما ذلك في أوله و أنه يجزئهما عن رمضان و أن قضية وجوب العمل بالظن أنه يجب عليهما ذلك و كذا من أخبراه إذا ظن صدقهما هـ “

“Our Shaykh Shihab ar-Ramli said and at-Tabalawi Al-Kabir agreed with him that it is obligatory for the haasib and munajjim to follow their findings and it suffices them. Imam Ramli said, ‘they can both act upon their findings including for establishing the end of Ramadhan as the reliable position is that they both can do it in the beginning of Ramadhan to establish it and it suffices. The issue of it being obligatory for them to follow what they have concluded is that it is necessary for them to follow their findings and also those who trust them.'”

In summary,

Ibn Hajar:

  • It is permissible for the munajjim (astronomer) and the hasib (Mathematician) to act upon their findings in but it wont suffice them for Ramadhan.
  • For the lay person, it is not allowed to follow the findings of others


  • It is permissible for them to act upon their findings and it suffices for Ramadhan.


  • It is obligatory for them to act upon their findings for establishing the beginning and end of the fasting month. The reliable position according to Ramli is that it also suffices for Ramadhan.
  • For the lay person, it is obligatory to follow them if one trusts their judgement.

In short, both of these opinions are valid and it is not a fair statement for anyone to say this is a Mu’tazili position.

Allah knows best.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.