Muwatta Imam Malik (Riwayat Ibn al-Qasim)

And with this same chain (it is narrated from Sayyiduna Ibn Umar, may Allah be pleased with them both) that the Messenger of Allah, peace and blessings be upon him, Usama bin Zaid, Bilal, and Uthman bin Talhah al-Hajmi, may Allah be pleased with them, entered the Ka'bah. They closed the door and stayed inside. Abdullah bin Umar, may Allah be pleased with them both, said: Then when the Prophet, peace and blessings be upon him, came out, I asked Sayyiduna Bilal, may Allah be pleased with him: What did the Messenger of Allah, peace and blessings be upon him, do inside? He replied: The Prophet, peace and blessings be upon him, stood in such a way that there was one pillar on his left, two pillars on his right, and three pillars behind him. In those days, the House of Allah had six pillars. Then the Prophet, peace and blessings be upon him, performed prayer, and there was a distance of three hand spans between him and the wall.