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
bayhaqi:8319 – Abū Bakr b. al-Ḥasan al-Qāḍī And ʾAbū Saʿīd b. Abū ʿAmr > Abū al-ʿAbbās Muḥammad b. Yaʿqūb > Muḥammad b. Isḥāq al-Ṣaghānī > Abū Ṣāliḥ > Muʿāwiyah b. Ṣāliḥ > Abū Ḥamzah > Sulaymān b. Mūsá > ʿAṭāʾ b. Abū Rabāḥ > Abū Hurayrah

[Machine] "He heard Abu Hurairah say that whoever experiences old age and is unable to fast during the month of Ramadan, then they must feed a poor person for each missed day, with a measure of wheat."  

البيهقي:٨٣١٩ – وَأَخْبَرَنَا أَبُو بَكْرِ بْنُ الْحَسَنِ الْقَاضِي وَأَبُو سَعِيدِ بْنُ أَبِي عَمْرٍو قَالَا ثنا أَبُو الْعَبَّاسِ مُحَمَّدُ بْنُ يَعْقُوبَ ثنا مُحَمَّدُ بْنُ إِسْحَاقَ الصَّغَانِيُّ ثنا أَبُو صَالِحٍ حَدَّثَنِي مُعَاوِيَةُ بْنُ صَالِحٍ أَنَّ أَبَا حَمْزَةَ حَدَّثَهُ عَنْ سُلَيْمَانَ بْنِ مُوسَى عَنْ عَطَاءِ بْنِ أَبِي رَبَاحٍ

أَنَّهُ سَمِعَ أَبَا هُرَيْرَةَ يَقُولُ مَنْ أَدْرَكَهُ الْكِبَرُ فَلَمْ يَسْتَطِعْ صِيَامَ شَهْرِ رَمَضَانَ فَعَلَيْهِ لِكُلِّ يَوْمٍ مُدٌّ مِنْ قَمْحٍ