The Case of One Who Vows to Fast a Certain Day or for Thanksgiving

8. A number of our people have narrated from Sahl ibn Ziyad from al-Hassan ibn Mahbub from ‘Abd Allah ibn Sinan who has said the following: “I once asked abu ’Abd Allah عليه السلام, about a man who fasts because of what he has timed upon himself or to fast of the sacred months and then one or two months pass during which he does not fast at all. He (the Imam) said, ‘He is not required to fast on a journey and there is not anything of Qada’ (compensatory fast) for optional fast except the three days that he would fast every month. He must not take it as obligatory except that I like you to continue with a good deed.’ He (the Imam) said, ’For the one committing himself to fast in the sacred months, fasting of three days, instead of fasting the whole of sacred month, is sufficient.’”