What should I do if the Mondays and Thursdays that I vowed to fast – in exchange for the fulfillment of my قسم (oath/pledge) – fall during the month of Ramadan, or on the day of Arafah, or on Eid? And is it necessary to feed ten poor people twice, or only once, as expiation for my oath?

Firstly: Vows of obedience must be fulfilled, and this includes the vow to fast on Mondays and Thursdays.

Secondly: It is by consensus not permissible to fast anything other than Ramadan during Ramadan, nor is it permissible to fast on the two Eid days and the days of Tashreeq.

Thirdly: If someone has vowed to fast on Mondays and Thursdays and Ramadan arrives, they should fast them with the intention of Ramadan. There is no compensatory fasting (qadaa') or expiation (kaffarah) required according to the Shafi'is and one narration from Ahmad, because Ramadan is not included in the vow. However, the Hanbalis hold that compensatory fasting and expiation are obligatory.

Fourthly: If the vowed day coincides with a day on which fasting is prohibited (such as Eid and the days of Tashreeq), then fasting is prohibited. According to the Hanbalis, compensatory fasting and expiation are obligatory. The Shafi'is have two opinions regarding compensatory fasting, the more prominent of which is that no compensatory fasting is required, and they do not require expiation.

Fifthly: If the vowed day coincides with the Day of Arafah, one should fast with the intention of fulfilling the vow, and it is hoped that they will receive the reward for Arafah.