Musnad Ahmad 1017:2

Ali ibn al-Hasan narrated to us, al-Husayn informed us, Abdullah ibn Buraydah narrated to us, from his father, that the Messenger of Allah (peace and blessings of Allah be upon him) was sitting on Hira, and with him were Abu Bakr, Umar, and Uthman. The mountain moved. The Messenger of Allah (peace and blessings of Allah be upon him) said: "Be still, Hira; for there is upon you none but a Prophet, or a Siddiq (truthful one), or a martyr."