The Fast of Summer

Once, during the journey of Hajj, Hajaj bin Yusuf stopped at a place between Makka-tul-Mukarrama and Madina-tul-Munawwara and had the lunch prepared. He then instructed his guard to bring a guest. When the guard left the tent, he spotted a Bedouin lying down. He woke him up and said, come, Hajaj bin Yusuf is calling you. When the Bedouin came, Hajaj bin Yusuf said, accept my invitation, wash your hands and sit down with me to eat. The Bedouin replied, please forgive me, prior to your invitation I have already accepted the invitation of someone else that is more generous and gracious than you. Hajaj bin Yusuf asked, whose invitation ? The Bedouin replied, The invitation of Allah ta'ala who has invited me to keep a fast and hence I have had fast. Hajaj asked, you have fast in such scorching heat ? The Bedouin replied, yes, inorder to save myself from the blazing heat of Judgment Day. Hajaj said, please eat now and make up for the fast tomorrow. The Bedouin immediately replied, can you guarantee me that I will be alive till tomorrow ? Hajaj replied, I m afraid I can’t. The pious Bedouin said I m afraid I can’t eat, and then he went away. 

(Rauz ur Riyaheen P::212)