Musnad Abu Ya'la al-Mawsili 117:4

'Abd al-A'la narrated to us, Hammad narrated to us, Thabit narrated to us, from Anas, that a man said: "O Messenger of Allah, a man loves a people but has not done their deeds." He said: "A person is with whom he loves." Hammad said: And he said in the hadith: "The Muslims did not rejoice at anything after Islam as they rejoiced at this."