Sahih al-Bukhari 1171

Narrated Mujahid:Somebody came to the house of Ibn `Umar and told him that Allah's Messenger (ﷺ) had entered the Ka`ba. Ibn `Umar said, "I went in front of the Ka`ba and found that Allah's Messenger (ﷺ) had come out of the Ka`ba and I saw Bilal standing by the side of the gate of the Ka`ba. I said, 'O Bilal! Has Allah's Apostle (ﷺ) prayed inside the Ka`ba?' Bilal replied in the affirmative. I said, 'Where (did he pray)?' He replied, '(He prayed) Between these two pillars and then he came out and offered a two rak`at prayer in front of the Ka`ba.' " Abu `Abdullah said: Abu Huraira said, "The Prophet (ﷺ) advised me to offer two rak`at of Duha prayer (prayer to be offered after sunrise and before midday). " Itban (bin Malik) said, "Allah's Messenger (ﷺ) and Abu Bakr, came to me after sunrise and we aligned behind the Prophet (ﷺ) and offered two rak`at