Musnad Ahmad 937:174

Rawh and Hashim narrated to us, they said: Sulayman ibn al-Mughirah narrated to us, Humayd ibn Hilal narrated to us. Hashim said: From Humayd, from Abdullah ibn al-Samit, he said: Abu Dharr said: I said: "O Messenger of Allah, a man loves a people but is unable to perform deeds like theirs?" He said: "You, O Abu Dharr, are with whom you love." I said: "Indeed, I love Allah and His Messenger." He said: "You, O Abu Dharr, are with whom you love." Hashim said: He said it to him three times: "You are with whom you love."