He reported God’s messenger as saying, “If anyone out of a desire to please God fasts for a day, God will remove him from jahannam as far as a crow flies from the time it is a young bird till it dies of old age.”
Ahmad transmitted it, and Baihaqi transmitted it in Shu'ab al-iman from Salama b. Qais.
He said that the Prophet used to fast on Mondays and Thursdays, and when someone remarked on this to him he said, “On Monday and Thursday God forgives every Muslim except two who are at variance, for He says they must be left till they make peace with one another.”
The Prophet came to visit me one day and asked if I had anything . When I said I had nothing he replied, “Then I shall observe a fast.” When he came to me another day and I told him I had been given a present of some hais* he said, “Show me it, for I began the day fasting.” Then he ate.
*A mixture of dates and clarified butter.
