Calculations

[Ahmad ibn Philip]

A lot is made of the moon sighting calculations being a bid'ah but what about the day to day prayer timing calendars? These are calculated as well. Is this not the same kind of bid'ah or at least similar?

[Mostafa]

That is because the moonsighting hadith specifically has the 'amr of sighting (ru'ya), and there exists ijma' on the invalidity of calculations. While the prayer timings are not subjugated to that 'amr and are therefore valid. A classical scholar mentioned this issue but I cant find the quote right now or remember his name, but if I find it I will post it inshaAllaah. This is parts of how my sheikh explained it to me. Have a great Ramadhan for those starting.

[rizwan]

In the Tafseer of Imam Al-Qurtabi, Ibn Nafi'e (ra) reported that Imam Malik bin Anas (ra) said: "If you see an Imam who does not begin and end fasting by way of sighting, but begins fasting by calculation, he should not be followed in prayer or emulated." The renowned scholar Ibn Al'Arabi said, "Some of our people erred when they reported that Imam Shaf'i relied on calculations." Ibn Al-'Arabi commented, "The report is baseless and false.

[Ibn 'Abbas]

Al-Imam al-Qarafi Wrote about this issue in "al-Furooq" .

The difference is that the 'Ilah of fasting is the one of two the sighting or completing sha'ban. While the 'ilah of praying is the merely Time, so the means are not considered.

The prophet said "soomu Li rooyatihi" and Laam in this context gives us the 'Ilah which is to see the moon.

من أجل ذا فنحو كي اذا فما .... ظهر لام ثمت الباعلما

And then he said "in ghumma aleykum fa akmiloo..."

So our prophet mentioned the hukm of completing sha'ban after a condition with 'faa' between the condition and hukm, and that gives the 'Ilah as stated in al-Maraqi

فالفاء للشارع فالفقيه.... فغيره يتبع بالشبيه

So the ilah of completing sha'ban is to not see the Moon.