Hadith.1941 - Ibn Bukayr narrated from Zurara, who said: "I asked Abu Abdullah عليه السلام about the extent of illness that permits a fasting person to break their fast and to pray sitting instead of standing. Imam عليه السلام said: 'Indeed, man is a witness over himself' (Surah Al-Qiyamah 75:14), and he knows best what he can bear."