Sayyiduna Sa'id bin Zayd (may Allah be pleased with him) said: I heard the Messenger of Allah (peace and blessings be upon him) while he (peace and blessings be upon him) was on (the mountain of) Hira; it began to shake, so he (peace and blessings be upon him) struck it with his foot, then said: "Be still, Hira! For there is none upon you but a Prophet, a Siddiq or a martyr." And with him (peace and blessings be upon him) at that time were these people: Abu Bakr, Umar, Uthman, Ali, Talhah, al-Zubayr, Sa'd, Abd al-Rahman bin Awf, and I, meaning himself.
Hadith Referenceالمعجم الكبير للطبراني / العشرة / 353