It is narrated from Sayyiduna Usamah bin Zayd (may Allah be pleased with them both) that one day the Messenger of Allah (peace and blessings be upon him) came to Hamzah bin Abd al-Muttalib but did not find him, so he asked his wife Inabah, who was from Banu al-Najjar. She said: "May my father be ransomed for you! He has just gone out intending to come to you; I think he missed you in one of the lanes of Banu al-Najjar. O Messenger of Allah! Will you not come in?" So he (peace and blessings be upon him) went in, and she set hays before him, and he (peace and blessings be upon him) ate some of it. Then she said: "O Messenger of Allah! May it be wholesome and pleasant for you! I myself wanted to come to you to congratulate you. Abu Umarah (Hamzah) told me that you have been given a river in Paradise called al-Kawthar." He (peace and blessings be upon him) said: "Yes, and its ground is of rubies, coral, chrysolite and pearls." She said: "I would love you to describe your Pond to me in your own words, so that I may hear it from you." He (peace and blessings be upon him) said: "It is as wide as the distance between Aylah and San'a'; in it there are jugs as many as the stars, and O daughter of Qahd, the dearest to me of those who come to it are your people," meaning the Ansar.
Hadith Referenceالمعجم الكبير للطبراني / باب الحاء / 2947