Musnad Ahmad

Hazrat Ubayy bin Ka'b (may Allah be pleased with him) narrates that Hazrat Abu Hurairah (may Allah be pleased with him) was very bold in this regard that he would ask the Holy Prophet (peace and blessings be upon him) such questions which others could not ask. So once he asked, "O Messenger of Allah! What was the first thing you saw regarding the matter of Prophethood?" The Holy Prophet (peace and blessings be upon him), upon hearing this question, sat up straight and said, "Abu Hurairah! You have asked a good question. I was ten years and a few months old, wandering in a forest, when suddenly I heard voices above my head. I looked up and saw a man saying to another, 'Is this the one?' The other replied, 'Yes!' Then both of them came before me with such faces as I had never seen on any creature before. A fragrance emanated from them which I had never smelled from any creature before, and they wore such clothes as I had never seen on anyone before. Both of them came walking towards me, and each of them took hold of one of my arms, but I did not feel any pain from this. Then one of them said to the other, 'Lay him down.' So they laid me down without any pulling or pain. Then one of them said to the other, 'Open his chest.' So he opened my chest before my eyes in such a way that neither blood came out nor did I feel any pain. Then the first said to the other, 'Take out rancor and envy from him.' So he took out something like a clot of blood and threw it away. Then he said to the other, 'Put gentleness and mercy into him.' So something like silver was brought (and poured into my chest). Then he moved the big toe of my right foot and said, 'Go, remain safe.' So I returned in such a state that I was soft-hearted towards the young and merciful towards the elders."