بسم الله الرحمن الرحيم
The prophet (ﷺ) said:
لاَ يَتَقَدَّمَنَّ أَحَدُكُمْ رَمَضَانَ بِصَوْمِ يَوْمٍ أَوْ يَوْمَيْنِ، إِلاَّ أَنْ يَكُونَ رَجُلٌ كَانَ يَصُومُ صَوْمَهُ فَلْيَصُمْ ذَلِكَ الْيَوْمَ
None of you should fast a day or two before the month of Ramadān unless he has the habit of fasting (and if his fasting coincides with that day) then he can fast that day (Sahīh al-Bukhārī 1914)
عَنْ أَبِي إِسْحَاقَ، عَنْ صِلَةَ، قَالَ كُنَّا عِنْدَ عَمَّارٍ فِي الْيَوْمِ الَّذِي يُشَكُّ فِيهِ فَأُتِيَ بِشَاةٍ فَتَنَحَّى بَعْضُ الْقَوْمِ فَقَالَ عَمَّارٌ مَنْ صَامَ هَذَا الْيَوْمَ فَقَدْ عَصَى أَبَا الْقَاسِمِ صلى الله عليه وسلم .
Abū Ishāq reported on the authority of Silah: We were with Ammār on the day when the appearance of the moon was doubtful. (The meat of) goat was brought to him. Some people kept away from (eating) it. Ammār said: He who fasts on this day disobeys Abul-Qāsim (meaning the Prophet) (ﷺ). (Abū Dawūd 2334. Declared Sahīh by Al-Albānī)
Shaykh Ibn ‘Uthaymīn said:
The prophet (ﷺ) prohibited that anyone should precede the fast of the month of Ramadān with fasting a day or two days, unless he has the habit of fasting on a particular day; such as Monday for example or if he fasts every other day and that happened to fall on the day or two days before Ramadān, then there is no harm in that due to the removal of the threat. (Sharh Umdatul-Ahkām 2/89)
Shaykh al-Fawzān said:
If the new moon is not sighted on the 30th (night) of Sha’bān due to cloudy skies or haze, then the following day (i.e. day of 30th Sha’bān) is known as the day of doubt (yawm al-shakk), for it could be the last day of Sha’bān or the first day of Ramadān. Most scholars are of the opinion that people should not fast the next day (i.e. 30th day of Sha’bān) based on the hadīths of the Prophet (ﷺ) ; ‘Fast when it is sighted and end the fast when it is sighted. If the sky is overcast, then estimate the period’ and in another narration ‘If the sky is overcast then complete Sha’bān as thirty days’ (Sahīh al-Bukhārī 1906 and 1907). (Summarised, Sharh Zād al-Mustaqni’ pg. 579)
Ibn Battal said:
A group held that it is not permissible to fast a voluntary fast on the last day of Sha’bān unless it coincides with a (habitual) fast he was observing. They took the apparent meaning of this hadīth [Bukhārī 1914], and this (opinion) was narrated on the authority of ‘Umar, ‘Alī, Ammār, Hudhayfah, and Ibn Mas’ūd. Among the tabi’īn are Sa’īd bin Al-Musayyab, Al-Sha’bī, Al-Nakha’ī [and Al-Hasan] and Ibn Sirīn, and this is the opinion of Al-Shafi’ī.
Ibn Abbās (1) and Abū Hurairah (2) used to command that Sha’bān and Ramadān be separated by breaking the fast by one or two days, just as they recommended that they separate the obligatory and voluntary prayers by speaking, standing up, moving forwards or moving backwards.
Ikrimah said: Whoever fasts on the day of doubt has disobeyed Allāh and His Messenger (ﷺ).
(Sharh Sahīh al-Bukhārī 4/32)
(1) Musannaf of ‘Abdul-Razzāq 7440.
(2) Musannaf of ‘Abdul-Razzāq 7441.
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