Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
Qurʾān Bukhārī Muslim Nasāʾī Abū Dāwūd Tirmidhī Ibn Mājah Mālik Aḥmad Dārimī Ḥākim Ibn Ḥibbān Ṭabarānī Nasāʾī's Kubrá Bayhaqī al-Luʾluʾ wa-al-Marjān Ibn Rajab's Fifty Riyāḍ al-Ṣāliḥīn Aḥmad's Zuhd Suyūṭī
quran:2:184 –

˹Fasting for˺ a limited number of days. So whoever among you is ill or on a journey ˹during them˺ - then an equal number of days ˹are to be made up˺. And upon those who are able ˹to fast, but with hardship˺ - a ransom ˹as substitute˺ of feeding a poor person ˹each day˺. And whoever volunteers excess - it is better for him. But to fast is best for you, if you only knew.  

For days (ayyāman, ‘days’, is in the accusative as the object of al-siyām, ‘the fast’, or of an implied yasūmū, ‘he fasts’) numbered, few or specific in number, that is, those of Ramadān, as will be mentioned below; God has specified a small number as a way of facilitating matters for those under the obligation; and if any of you, during the month, be sick, or be on a journey, in which prayers are shortened, or if one is strained by the fast in both cases and breaks it, then a number of other days, equal to the ones during which he broke his fast — let him fast them instead; and for those who are, not, able to do it, ˹to fast˺ on account of old age or chronic illness, a redemption: which is, the feeding of a poor man, with about the same amount one consumes in a given day, that is, one mudd measure of the principal food of that town each day (a variant reading has ˹genitive˺ fidyatin as an explicative clause. It is also said that the ˹lā˺ negation of the verb ˹yutīqūnahu˺ is not actually implied, because at the very beginning of Islam, they could choose between fasting or offering the redemption; but later on this was abrogated by fixing the Fast ˹as an obligation˺, where God says, So let those of you, who are present at the month, fast it ˹Q. 2:185˺: Ibn ‘Abbās said ˹by way of qualification˺ ‘Except for the pregnant one and the one breastfeeding, if they break their fast out of concern for the child; in the case of these two, the verse remains valid and has not been abrogated’). For him who volunteers good, by offering more than the minimum amount mentioned for the redemption; that, volunteering, is good for him; but that you should fast (wa-an tasūmū is the subject) is better for you (khayrun lakum is its predicate), than breaking the fast and paying the redemption, if you but knew, that this is better for you, then do it.
القرآن:٢:١٨٤ –

أَيَّامًا مَعْدُودَاتٍ ۚ فَمَنْ كَانَ مِنْكُمْ مَرِيضًا أَوْ عَلَىٰ سَفَرٍ فَعِدَّةٌ مِنْ أَيَّامٍ أُخَرَ ۚ وَعَلَى الَّذِينَ يُطِيقُونَهُ فِدْيَةٌ طَعَامُ مِسْكِينٍ ۖ فَمَنْ تَطَوَّعَ خَيْرًا فَهُوَ خَيْرٌ لَهُ ۚ وَأَنْ تَصُومُوا خَيْرٌ لَكُمْ ۖ إِنْ كُنْتُمْ تَعْلَمُونَ  

{أيَّاما} نصب بالصيام أو يصوموا مقدرا {معدودات} أي قلائل أو مؤقتات بعدد معلوم وهي رمضان كما سيأتي وقلَّله تسهيلا على المكلفين {فمن كان منكم} حين شهوده {مريضا أو على سفر} أي مسافرا سفر القصر وأجهده الصوم في الحالين فأفطر {فعدَّة} فعليه عدة ما أفطر {من أيام أخر} يصومها بدله {وعلى الذين} لا {يطيقونه} لكبر أو مرض لا يرجى برؤه {فدية} هي {طعام مسكين} أي قدر ما يأكله في يومه وهو مدٌ من غالب قوت البلد لكل يوم، وفي قراءة بإضافة فدية وهي للبيان وقيل لا غير مقدرة وكانوا مخيرين في صدر الإسلام بين الصوم والفدية ثم نسخ بتعيين الصوم بقوله من شهد منكم الشهر فليصمه، قال ابن عباس: إلا الحامل والمرضع إذا أفطرتا خوفا على الولد فإنها باقية بلا نسخ في حقهما {فمن تطوع خيرا} بالزيادة على القدر المذكور في الفدية {فهو} أي التطوع {خير له، وأن تصوموا} مبتدأ خبره {خير لكم} من الإفطار والفدية {إن كنتم تعلمون} أنه خير لكم فافعلوه.

See similar narrations below:

Collected by Abū Dāwūd
abudawud:2316 – Aḥmad b. Muḥammad > ʿAlī b. Ḥusayn from his father > Yazīd al-Naḥwī > ʿIkrimah

Ibn ‘Abbas explain the Qur’anic verse “For those who can do it(with hardship) is a ransom, the feeding of one, that is indigent” said “If one of them wished to pay ransom by providing food to an indigent person he could pay ransom.. Thus, his fast was complete. Allaah, the Exalted pronounced “But he that will give more of his own free will, it is better for him”. Again he pronounced “So every one of you who is present (at his home) during that month should spend it in fasting.” But, if anyone is ill or on a journey the prescribed period (should be made up) by days later.  

أبو داود:٢٣١٦ – حَدَّثَنَا أَحْمَدُ بْنُ مُحَمَّدٍ حَدَّثَنِي عَلِيُّ بْنُ حُسَيْنٍ عَنْ أَبِيهِ عَنْ يَزِيدَ النَّحْوِيِّ عَنْ عِكْرِمَةَ عَنِ ابْنِ عَبَّاسٍ { وَعَلَى الَّذِينَ يُطِيقُونَهُ فِدْيَةٌ طَعَامُ مِسْكِينٍ } فَكَانَ مَنْ شَاءَ مِنْهُمْ

أَنْ يَفْتَدِيَ بِطَعَامِ مِسْكِينٍ افْتَدَى وَتَمَّ لَهُ صَوْمُهُ فَقَالَ { فَمَنْ تَطَوَّعَ خَيْرًا فَهُوَ خَيْرٌ لَهُ وَأَنْ تَصُومُوا خَيْرٌ لَكُمْ } وَقَالَ { فَمَنْ شَهِدَ مِنْكُمُ الشَّهْرَ فَلْيَصُمْهُ وَمَنْ كَانَ مَرِيضًا أَوْ عَلَى سَفَرٍ فَعِدَّةٌ مِنْ أَيَّامٍ أُخَرَ }