Is it obligatory for Muslims to observe full day of fasting where days are very long?

Sources

• ✓ 2:183 · Al-Baqara

  2:183 · Muhammad Marmaduke Pickthall

  يَٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوا۟ كُتِبَ عَلَيْكُمُ ٱلصِّيَامُ كَمَا كُتِبَ عَلَى ٱلَّذِينَ مِن قَبْلِكُمْ لَعَلَّكُمْ تَتَّقُونَ

  O ye who believe! Fasting is prescribed for you, even as it was prescribed for those before you, that ye may ward off (evil);

• ✓ 2:185 · Al-Baqara

  2:185 · Muhammad Marmaduke Pickthall

  شَهْرُ رَمَضَانَ ٱلَّذِىٓ أُنزِلَ فِيهِ ٱلْقُرْءَانُ هُدًۭى لِّلنَّاسِ وَبَيِّنَٰتٍۢ مِّنَ ٱلْهُدَىٰ وَٱلْفُرْقَانِ ۚ فَمَن شَهِدَ مِنكُمُ ٱلشَّهْرَ فَلْيَصُمْهُ ۖ وَمَن كَانَ مَرِيضًا أَوْ عَلَىٰ سَفَرٍۢ فَعِدَّةٌۭ مِّنْ أَيَّامٍ أُخَرَ ۗ يُرِيدُ ٱللَّهُ بِكُمُ ٱلْيُسْرَ وَلَا يُرِيدُ بِكُمُ ٱلْعُسْرَ وَلِتُكْمِلُوا۟ ٱلْعِدَّةَ وَلِتُكَبِّرُوا۟ ٱللَّهَ عَلَىٰ مَا هَدَىٰكُمْ وَلَعَلَّكُمْ تَشْكُرُونَ

  The month of Ramadan in which was revealed the Qur'an, a guidance for mankind, and clear proofs of the guidance, and the Criterion (of right and wrong). And whosoever of you is present, let him fast the month, and whosoever of you is sick or on a journey, (let him fast the same) number of other days. Allah desireth for you ease; He desireth not hardship for you; and (He desireth) that ye should complete the period, and that ye should magnify Allah for having guided you, and that peradventure ye may be thankful.

• ✓ Tafsir Ibn Kathir on 2:183

  Sunni

  Tafsir Ibn Kathir · 2:183

  Allah addresses the believers of this community, commanding them to observe fasting, defined as refraining from food, drink, and intimate relations with sincere intention for Allah's sake. This practice purifies the soul, cleanses it from harmful mixtures and immoral traits, promoting spiritual purification. Allah imposed fasting upon them just as it was prescribed for the communities before them, providing a model to follow. These believers are urged to strive to perform this obligation more perfectly than those before, illustrating the principle that for each community Allah has set distinct laws and ways, testing them to compete in doing good. The verse states: "O you who have believed, fasting is prescribed for you as it was prescribed for those before you, that you may become righteous." This indicates fasting is a means of self-purification and restraining the devil's paths. Authentic hadith explain that the Prophet ﷺ said: "O young men, whoever among you can marry, let him marry; and whoever cannot, let him fast for fasting is a shield for him." The amount of fasting imposed is not every day but limited days to avoid hardship and ensure endurance. Initially, at the start of Islam, fasting was three days in every month; this was later abrogated and replaced by fasting the month of Ramadan exclusively. This practice existed from the time of Noah until Allah replaced it. Scholars like al-Hasan al-Basri noted that fasting was prescribed in every nation, sometimes for a whole month or certain known days. From reports of Abdullah ibn Umar and others, the Prophet ﷺ stated that Ramadan fasting was written upon previous nations as well. According to al-Razi and others, among the predecessor nations, fasting meant refraining from food, drink, and marital relations from dusk to dawn. There is agreement that fasting was initially practiced intermittently and later made obligatory specifically for Ramadan. Sick persons or travelers are permitted to break the fast and make up days later to ease hardship. For the healthy resident able to fast, the choice between fasting or feeding a poor person existed initially, though fasting is superior. This is supported by both the Quranic injunction and prophetic sayings. The Prophet ﷺ observed three phases in the establishment of prayer and fasting upon arriving in Medina: prayer direction shifted from Jerusalem to Mecca; initially, fasting was three days each month plus Ashura; finally, Ramadan fasting was commanded as mandatory. Regarding marital relations, initially, spouses engaged in it so long as they had not slept; if sleeping occurred, fasting began. This was later clarified by a revelation permitting marital relations during the night of fasting. There are legal narrations confirming the abrogation of earlier rulings allowing optional fasting or feeding a poor person as a substitute. The final ruling obligates fasting for the healthy person and exempts the elderly unable to fast; for them, feeding a poor person for each day they miss is prescribed as compensation (fidya), though some scholars differ on its obligatory nature for very weak elderly. Pregnant and breastfeeding women fearing harm to themselves or their child have diverse rulings: some say they can break the fast and compensate by feeding and making up days; others restrict compensation; some allow only making up later without fidya. This detailed matter is treated separately. All praise is due to Allah for these rulings and His favors.

• ✓ Sahih Muslim 13:73

  Sunni SAHIH

  Sahih Muslim · Book 13, Hadith 73 · Narrated by Abu Huraira

  The Messenger of Allah (ﷺ) said, "Beware of fasting continuously (without breaking the fast at sunset)." They said, "But you fast continuously, O Messenger of Allah!" He said, "You are not like me; I spend the night and my Lord feeds me and gives me drink. So, take upon yourselves only the deeds you can bear."