He heard the Messenger of Allah ﷺ say, "There is no servant who fasts a day in the path of Allah except that Allah
will distance his face from the Fire by seventy years for that day."
أخبرنا محمد بن عبد الله بن عبد الحكم عن شعيب قال أنبأنا الليث عن ابن الهاد عن سهيل عن ابن أبي عياش
أنه سمع رسول الله ﷺ يقول ما من عبد يصوم يوما في سبيل الله عز وجل إلا بعد الله عز وجل بذلك اليوم وجهه عن النار سبعين خريفا
Reported by Muslim, Fasting, Chapter on the merit of fasting in the cause of Allah for one who is able to bear it, etc., hadith no. 1153, from the hadith of Layth bin Saad, and by Bukhari, Jihad and Expeditions, Chapter on the merit of fasting in the cause of Allah, hadith no. 2840, from the hadith of Suhayl bin Abu Salih, with the same wording. It is also found in Kubra, hadith no. 2556. See the following hadith.