Musnad Ahmad 937:262

Yazid narrated to us, Mas'udi informed us, from Abu 'Umar al-Shami, from 'Ubayd ibn al-Khashkhash, from Abu Dharr, who said: I came to the Messenger of Allah (peace and blessings of Allah be upon him) while he was in the mosque, so I sat with him. He said to me: "O Abu Dharr, have you prayed?" I said: No. He said: "Stand and pray." He said: So I stood and prayed, then I came to him and sat with him. He said: "O Abu Dharr, seek refuge in Allah from the evil of the devils of mankind and the jinn." He said: I said: O Messenger of Allah, do humans have devils? He said: "Yes." "O Abu Dharr, shall I not guide you to a treasure from the treasures of Paradise?" He said: I said: Yes, may my father and mother be sacrificed for you. He said: "Say: *La hawla wa la quwwata illa billah* (There is no power and no strength except by Allah), for it is a treasure from the treasures of Paradise." He said: I said: O Messenger of Allah, what is the prayer? He said: "The best subject; whoever wishes may increase, and whoever wishes may decrease." He said: I said: What is fasting, O Messenger of Allah? He said: "A sufficient obligation." He said: I said: O Messenger of Allah, what is charity? He said: "Multiplied many times over, and with Allah is more." He said: I said: Which is best, O Messenger of Allah? He said: "The effort of one who has little, or [giving] secretly to a poor person." I said: Which of what Allah, the Mighty and Majestic, revealed to you is the greatest? He said: "{Allah - there is no deity except Him, the Ever-Living, the Sustainer of [all] existence} [Al-Baqarah: 255]," until he finished the verse. I said: Which of the prophets was the first? He said: "Adam." I said: Was he a prophet, O Messenger of Allah? He said: "Yes, a prophet spoken to [by Allah]." I said: How many were the messengers, O Messenger of Allah? He said: "Three hundred and fifteen, a large gathering."