It is narrated from Jubair bin Huwairith: "I saw Abu Bakr (may Allah be pleased with him) standing on the Qazah mountain, and he was saying: O people! Let there be full daylight. Then he departed from there, and it is as if I am looking at his thigh, with which he was striking his camel like a stick."
Hadith Referenceمسند الإمام الشافعي / كتاب الحج / 1009