Abu Junaydah al-Fihri narrates from his father, who narrates from his grandfather (may Allah be pleased with him), that the Messenger of Allah (peace and blessings be upon him) said: "Whoever gives water to a thirsty person and quenches his thirst, a gate of Paradise is opened for him and it is said to him: Enter through it. And whoever feeds a hungry person until he is full and gives water to a thirsty person until his thirst is quenched, all the gates of Paradise are opened for him and it is said to him: Enter through whichever of them you wish."
Hadith Referenceالمعجم الكبير للطبراني / مسند من يعرف بالكنى / 19142