Sahih al-Bukhari 1554
صحيح البخاري#1554Sahihحَدَّثَنَا سُلَيْمَانُ بْنُ دَاوُدَ أَبُو الرَّبِيعِ، حَدَّثَنَا فُلَيْحٌ، عَنْ نَافِعٍ، قَالَ كَانَ ابْنُ عُمَرَ ـ رضى الله عنهما ـ إِذَا أَرَادَ الْخُرُوجَ إِلَى مَكَّةَ ادَّهَنَ بِدُهْنٍ لَيْسَ لَهُ رَائِحَةٌ طَيِّبَةٌ، ثُمَّ يَأْتِي مَسْجِدَ الْحُلَيْفَةِ فَيُصَلِّي ثُمَّ يَرْكَبُ، وَإِذَا اسْتَوَتْ بِهِ رَاحِلَتُهُ قَائِمَةً أَحْرَمَ، ثُمَّ قَالَ هَكَذَا رَأَيْتُ النَّبِيَّ صلى الله عليه وسلم يَفْعَلُ.
Narrated Nafi`:Whenever Ibn `Umar intended to go to Mecca he used to oil himself with a sort of oil that had no pleasant smell, then he would go to the Mosque of Al-Hulaifa and offer the prayer, and then ride. When he mounted well on his Mount and the Mount stood up straight, he would proclaim the intention of assuming Ihram, and he used to say that he had seen the Prophet (ﷺ) doing the same
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 25:40