It is narrated from Sayyiduna Anas (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) once said: "Shall I not tell you about the best houses of the Ansar? Banu Najjar, then Banu Abd al-Ashhal, then Harith bin Khazraj, then Banu Sa'idah." And he said: "There is goodness upon goodness in every house of the Ansar."
Hadith Referenceمسند احمد / مسند الخلفاء الراشدين / 392