Nasai

(1) This narration of Usamah radi Allahu anhu is also found in Sahih Muslim, in which the performance of prayer is negated. It is possible that, for some reason, Usamah radi Allahu anhu was not aware of the Prophet’s prayer. However, in Musnad Ahmad (5/304, and its chain is authentic), there is a narration from Usamah radi Allahu anhu himself that the Prophet performed prayer in the House of Allah (Baytullah). It is possible that a reliable person informed him, which led him to be certain. The first narration is according to his own knowledge. As a principle, when there is a conflict between negation and affirmation, affirmation is given preference, because it is possible that the one negating was unaware or forgot, etc.

(2) “This is the qiblah,” meaning the Ka‘bah is the qiblah.

(3) These narrations are regarding the conquest of Makkah, but from other narrations it is known that the Prophet also entered the House of Allah (Baytullah) on the occasion of the Farewell Pilgrimage (Hajjat al-Wada‘). And later, he also expressed regret that perhaps people might consider it a Sunnah and thereby fall into hardship.