Sawm, or fasting, is one of the fundamental acts of worship in Islam, prescribed as a means to develop mindfulness of Allah (taqwa). It is a spiritual practice that involves abstaining from food, drink, and other physical needs from dawn to sunset. The Quran emphasizes its universal nature, as it was prescribed for previous communities as well. Fasting aims to purify the soul, foster self-discipline, and enhance gratitude, serving as a path to spiritual growth and a reminder of Allah’s blessings and guidance.

You who believe, fasting is prescribed for you, as it was prescribed for those before you, so that you may be mindful of God.(Quran 2:183) 

It was in the month of Ramadan that the Quran was revealed as guidance for mankind, clear messages giving guidance and distinguishing between right and wrong. So any one of you who is present that month should fast, and anyone who is ill or on a journey should make up for the lost days by fasting on other days later. God wants ease for you, not hardship. He wants you to complete the prescribed period and to glorify Him for having guided you, so that you may be thankful. (Quran 2:185) 

We read in Mani al Akhbar, H818:

حدثنا أبو الحسن، قال: حدثنا علي بن أحمد الطبري، قال: حدثنا أبو سعيد، قال: حدثنا خراش، قال: حدثنا مولاي أنس بن مالك قال: قال رسول الله صلى الله عليه وآله: من صام يوما تطوعا فلوا عطي ملء الأرض ذهبا ما وفي أجره دون يوم الحساب. - يعني أن ثواب الصوم ليس بمقدر كما قدرت الحسنة بعشر أمثالها قال رسول الله صلى الله عليه وآله: قال الله عز وجل: كل أعمال ابن آدم بعشرة أضعافها إلى سبع مائة ضعف إلا الصبر فإنه لي وأنا أجزي به فثواب الصبر مخزون في علم الله عز وجل، والصبر الصوم -.

91.    We were told by Abu’l-Hasan, that he said: We were told by Ali bin Ahmad al-Tabari, that he said: We were told by Abu Sa’eed, that he said: We were told by Khirash, that he said: We were told by my master, Anas bin Malik, that he said: The Messenger of Allah, Allah’s blessings be upon him and his Family, said: The one who fasts a day voluntarily, if he is given the amount of what fills the earth with gold, his reward will not be fulfilled as compared to that of the Day of Reckoning. It means that the reward for fasting is not estimated like how one good deed is estimated by ten the likes of it. The Messenger of Allah, Allah’s blessings be upon him and his Family, said: Allah, Exalted and Glorious is He, said: All the deeds of the son of Adam are by ten the likes of them until seven hundred the likes of, except for patience, for indeed, it is for Me, and I will reward for it. Thus, the reward for patience is concealed in the Knowledge of Allah, Exalted and Glorious is He, and patience is fasting.

We read in mani al akhbar, H612:

حدثنا أبو نصر محمد بن أحمد بن تميم السرخسي الفقيه بسرخس، قال: حدثنا أبو لبيد محمد بن إدريس الشامي، قال: حدثنا هاشم بن عبد العزيز المحرمي ، قال: حدثنا عبد الرزاق، عن معمر، عن الجريري، عن أبي العلاء بن الشخير، عن نعيم بن قعنب، قال: أتيت الربذة ألتمس أبا ذر، فقالت لي امرأته: ذهب يمتهن . قال: فإذا أبو ذر قد أقبل يقود بعيرين قد قطر أحدهما بذنب الاخر قد علق في عنق كل واحد منهما قربة، قال: فقمت فسلمت عليه ثم جلست فدخل منزله وكلم امرأته بشئ فقال: أف أما تزيدين على ما قال رسول الله صلى الله عليه وآله: " إنما المرأة كالضلع إن أقمتها كسرتها وفيها بلغه " ثم جاء بصحفة فيها مثل القطاة فقال: كل فإني صائم، ثم قام فصلى ركعتين ثم جاء فأكل. قال: فقلت: سبحان الله من ظننت أن يكذبني من الناس فلم أظن أنك تكذبني. قال: وما ذاك؟ قلت إنك قلت لي إنك صائم ثم جئت فأكلت! قال: وأنا الآن أقوله، إني صمت من هذا الشهر ثلاثا فوجب لي صومه وحل لي فطره.

1.    We were told by Abu Nasr, Muhammed bin Ahmad bin Tamim al-Sarakhsi, the jurist, in Sarakhs, that he said: We were told by Abu Lubaid, Muhammedbin Idrees al-Shami, that he said: We were told by Hashim bin Abdul-Aziz al-Muharrami, that he said: We were told by Abdul-Razzaq, from Mu’ammar, from al-Jareeri, from Abu’l-‘Alaa’ bin Saheer, from Na’eem bin Qa’nab, that he said: I came to Al-Rabadha, seeking Abu Dharr, and his woman said to me: He went to seek a profession. He said: Suddenly, Abu Dharr approached whilst leading two camels, of which one had aligned to the tail of the other, and he had hanged a waterskin on the neck of each one of them. He said: Then I stood up and sent peace upon him, and then I sat down, and he entered his home and spoke something to his woman, and then said: Uff! Will you not add to what Allah’s Messenger, Allah’s blessings be upon him and his Family: «A woman is only like a rib; if you raise it, you break it, and in her is adequacy»? Then he came with a plate that had the like of a sand grouse, and he said: Eat, for I am fasting. Then he stood up and prayed two rak’at [1], and then he came and ate. He said: So I said: Glory be to Allah, as I had assumed that people would lie to me, I did not assume that you will lie to me. He said: And what is that? I said: You said to me that you are fasting, and then you came and ate. He said: And I am now saying the same. I fasted three (days) of this month, hence, its (reward for) fasting has been written to me, and it is permissible for me to break the fast during it.

we read in Thawab al amal wa iqab al amal, H290:

أَبِی ره قَالَ حَدَّثَنَا سَعْدُ بْنُ عَبْدِ اللَّهِ عَنْ مُحَمَّدِ بْنِ الْحُسَیْنِ عَنْ صَالح بنِ عُقْبَهَ عَنْ جَمِیلِ بْنِ دَرَّاجٍ قَالَ قَالَ أَبُو عَبْدِ اللَّهِ ع مَنْ دَخَلَ عَلَی أَخِیهِ وَ هُوَ صَائِمٌ فَأَفْطَرَ عِنْدَهُ وَ لَمْ یُعْلمهُ بِصَوْمِهِ فَیَمُنَّ عَلَیْهِ کَتَب اللهُ لَهُ صَوْمَ سَنَهٍ.

2.  Imam Ja’far Sadiq (a.s.) says, “One who goes to a brother in faith fasting and does Iftar at his house and does not tell him about his fast Allah grants him the reward of fasting for a year.”

We read in kitab al khisal H1194:

24-5 حدثنا أبي رضي الله عنه قال: حدثنا سعد بن عبد الله قال: حدثني موسى ابن جعفر البغدادي، عن محمد بن جمهور، عن عبد الله بن عبدالرحمن، عن محمد بن أبي حمزة، عن أبي عبد الله عليه السلام قال:من قال في كل يوم من شعبان سبعين مرة: "أستغفر الله الذي لا إله إلا هو الرحمن الرحيم، الحي القيوم، وأتوب إليه" كتب في الافق المبين، قال: قلت: وما الافق المبين؟ قال: قاع بين يدي العرش فيها أنهار تطرد فيه من القدحان عدد النجوم

24-5 (The compiler of the book narrated) that his father - may God be pleased with him - narrated that Sa’ed ibn Abdullah quoted Musa ibn Ja’far al-Baghdady, on the authority of Muhammad ibn Jumhoor, on the authority of Abdullah ibn Abdul Rahman, on the authority of Muhammad ibn Abi Hamzih, on the authority of Aba Abdullah as-Sadiq (MGB), “Whoever says ‘I ask for forgiveness by God - who is the Beneficent the Merciful the Living the Standing - and I repent to Him (‘Istaqfurallah al’lazi la illaha illahuval Rahman ar-Rahim al-Hayel Qayyum va Atubu ellayh’) seventy times on every day of the month of Sha’aban, his name will be recorded on the Clear Horizon. ’”The narrator said, “I asked, ‘What is the Clear Horizon?’ The Imam (MGB) replied, ‘It is a plain in front of the Throne where there are many streams in which is poured as many cups as there are stars.’”