1. Muhammad bin Musa al-Mutawakkil narrated to me, from Abdullah bin Ja'far al-Himyari, from Ahmad bin Muhammad bin 'Isa, form al-Hassan bin Mahbub, from Jamil bin Salih, from Muhammad bin Marwan, from abu 'Abdillah عليه السلام who said: "The Messenger of Allah صلى الله عليه وعلى آله وسلم used to fast until it was said he does not break his fast (he does not eat). Then he would fast for a day and break his fast on another day. After that, he would fast on Monday and Thursday. Furthermore, he would fast on three days in the month – Thursday in the start of the month, Wednesday in the middle of the month, and Thursday in the end of the month. He used to say, 'This is the perpetual fasting.'" My father عليه السلام used to say, "No one is more detestable to me than a man who is told that the Messenger of Allah صلى الله عليه وعلى آله وسلم used to do so-and-so, and he says, 'Allah will not punish me for doing ijtihad in prayer,' as if he sees that the Messenger of Allah صلى الله عليه وعلى آله وسلم has left some excellent deeds due to weakness."