" مَنْ صَامَ يَوْمًا فِي سَبِيلِ اللَّهِ بَاعَدَ اللَّهُ بِذَلِكَ الْيَوْمِ النَّارَ عَنْ وَجْهِهِ سَبْعِينَ خَرِيفًا "
It was narrated that Abu Saeed Al-Khudri said: "The Messenger of Allah said: Whoever fasts a day in the cause of Allah, Allah will separate his face (a distance of) seventy autumns from the fire in return for that day."