It is narrated from Sayyiduna Uqbah bin Amir (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) went out one day and prayed over the people of Uhud just as he would pray (the funeral prayer) over the deceased. Then he went to the pulpit and said: "I will go ahead of you to the Pool, and I am a witness over you. By Allah, I am looking at my Pool right now. I have been given the keys of (the treasures of) the earth. By Allah, I do not fear for you that you will associate partners with Allah after me, but I fear for you that you will compete with one another in pursuit of the world."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 14839