Musannaf Ibn Abi Shaybah 9146 — What is mentioned on the excellence

Sayyiduna Abu Musa (may Allah be pleased with him) said: Once we were travelling by sea, and we had raised our sails. No island was visible to us, nor could we see anything else. Then we heard a voice: "O people of the ship! Stop, and I will tell you something." We stood up and began to look, but we saw nothing. The caller called out seven times. The seventh time I stood up and said: "Whoever you are, tell us what you want to tell us; you see our condition and know that we cannot stop for you." He said: "I wish to inform you of a decree of Allah Almighty which He has made binding upon Himself: whoever makes himself thirsty for the sake of Allah on a hot day, Allah Almighty will quench his thirst on the Day of Resurrection."
In the narration of Abu Usamah there is the addition: After that, whenever there was a long day, you would always find Sayyiduna Abu Musa fasting.