The Limit of Illness That Exempts One from Fasting

8. Ali ibn Ibrahim has narrated from Muhammad ibn ‘Isa from Yunus ibn Shu’ayb from Muhammad ibn Muslim who has said the following: “I once asked abu ‘ Abd Allah عليه السلام, about the limit of the illness that weakens one when fasting. He (the Imam) said, ‘It is up to him to decide; he knows better about his soul and when he is strong he can then fast.’”