Narrated Mujahid: Someone came to Ibn `Umar and said, "Here is Allah's Apostle entering the Ka`ba." Ibn `Umar said, "I went there but the Prophet had come out of the Ka`ba and I found Bilal standing between its two doors. I asked Bilal, 'Did the Prophet pray in the Ka`ba?' Bilal replied, 'Yes, he prayed two rak`at between the two pillars which are to your left on entering the Ka`ba. Then Allah's Apostle came out and offered a two-rak`at prayer facing the Ka`ba.' "
Hadith Referenceصحيح البخاري / كتاب الصلاة / 397
Hadith Gradingمحدثین:أحاديث صحيح البخاريّ كلّها صحيحة
Narrated Nafi`: `Abdullah bin `Umar said, "Allah's Apostle entered the Ka`ba along with Usama bin Zaid, Bilal and `Uthman bin Talha Al-Hajabi and closed the door and stayed there for some time. I asked Bilal when he came out, 'What did the Prophet do?' He replied, 'He offered prayer with one pillar to his left and one to his right and three behind.' In those days the Ka`ba was supported by six pillars." Malik said: "There were two pillars on his (the Prophet's) right side."
Hadith Referenceصحيح البخاري / كتاب الصلاة / 505
Hadith Gradingمحدثین:أحاديث صحيح البخاريّ كلّها صحيحة
Narrated Qais: Bilal said to Abu Bakr, "If you have bought me for yourself then keep me (for yourself), but if you have bought me for Allah's Sake, then leave me for Allah's Work."
Hadith Referenceصحيح البخاري / كتاب فضائل الصحابة / 3755
Hadith Gradingمحدثین:أحاديث صحيح البخاريّ كلّها صحيحة