"Messenger of Allah ﷺ, Usama bin Zaid, Bilal, and ʿUthman bin abu Talha entered the Kaʿba and then closed its door. When they opened the door I was the first person to enter (the Kaʿba). I met Bilal and asked him, "Did Messenger of Allah ﷺ offer a prayer inside (the Kaʿba)?" Bilal replied in the affirmative and said, "(The Prophet ﷺ offered the prayer) in between the two right pillars."  

أَنَّهُ قَالَ دَخَلَ رَسُولُ اللَّهِ ﷺ الْبَيْتَ هُوَ وَأُسَامَةُ بْنُ زَيْدٍ وَبِلاَلٌ وَعُثْمَانُ بْنُ طَلْحَةَ فَأَغْلَقُوا عَلَيْهِمْ فَلَمَّا فَتَحُوا كُنْتُ أَوَّلَ مَنْ وَلَجَ فَلَقِيتُ بِلاَلاً فَسَأَلْتُهُ هَلْ صَلَّى فِيهِ رَسُولُ اللَّهِ ﷺ قَالَ نَعَمْ بَيْنَ الْعَمُودَيْنِ الْيَمَانِيَيْنِ