Q: Who fasts on any of the Thursdays, Fridays and Saturdays consecutively (meaning all 3 days together) of every or any of the Sacred Months, he will receive the reward of making ibadah for 700 years. There are 4 months which are Sacred, they are: Rajab, Dhul Qi’dah, Dhul Hijjah, and Muharram.
Also its been related that whoever fasts three consecutive days in the Sacred Months, that is Thursday, Friday and Saturday, Allah will distance him from the Fire.
In Another It is mentions in a Hadith that the person who keeps three fasts in the Sacred months, on Thursday, Friday and Saturday, he will receive the reward of making ibadah for two years. That is, on the Day of Judgement it will be written in his book of deeds that he had made ibadah for two years in return for these three days of fasting. Another version says: One who fasts in the sacred months on three days:
Thursday, Friday and Saturday Allah writes for him the reward of worship of 900 years for fasting during the day and remaining awake in night. this is mentioned in Tabarani In these months, the reward for good deeds is multiplied; and though committing sins is forbidden at all times, it is even more forbidden during these months.
I just wanted to know the authenticity and the reference for these books.
A: This is what we have so far come across.
Hadeeth of receiving the reward of 2 years of ibaadat. Al-Mu`jamul Awsat, vol. 2, p. 219:
عن راشد أبي محمد المدني قال سمعت أنس بن مالك يقول قال رسول الله صلى الله عليه وسلم : من صام ثلاثة أيام من شهر حرام الخميس والجمعة والسبت كتب له عبادة سنتين.
Hadeeth of receiving the reward of making ibaadat for 700 years. Mukhtasar Tareekh Damishq, vol. 9, p. 61
وحدث زهير أيضاً عن أبي يعلى محمد بن أحمد بن عبيد الأقطع السلمي الملطي بسنده عن أنس قال: قال رسول الله صلى الله عليه وسلم: من صام في كل شهر حرام الخميس والجمعة والسبت كتب له عبادة سبع مئة سنة.
And Allah Ta’ala (الله تعالى) knows best.