Sahih al-Bukhari, Hadith 2610 ⓘ
Narrated Ibn `Umar: That he was in the company of the Prophet on a journey, riding a troublesome camel belonging to `Umar. The camel used to go ahead of the Prophet, so Ibn `Umar's father would say, "O `Abdullah! No one should go ahead of the Prophet." The Prophet said to him, "Sell it to me." `Umar said to the Prophet "It is for you." So, he bought it and said, "O `Abdullah! It is for you, and you can do with it what you like."
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مُحَمَّدٍ، حَدَّثَنَا ابْنُ عُيَيْنَةَ، عَنْ عَمْرٍو، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ أَنَّهُ كَانَ مَعَ النَّبِيِّ صلى الله عليه وسلم فِي سَفَرٍ فَكَانَ عَلَى بَكْرٍ لِعُمَرَ صَعْبٍ، فَكَانَ يَتَقَدَّمُ النَّبِيَّ صلى الله عليه وسلم فَيَقُولُ أَبُوهُ يَا عَبْدَ اللَّهِ لاَ يَتَقَدَّمِ النَّبِيَّ صلى الله عليه وسلم أَحَدٌ. فَقَالَ لَهُ النَّبِيُّ صلى الله عليه وسلم " بِعْنِيهِ ". فَقَالَ عُمَرُ هُوَ لَكَ. فَاشْتَرَاهُ ثُمَّ قَالَ " هُوَ لَكَ يَا عَبْدَ اللَّهِ، فَاصْنَعْ بِهِ مَا شِئْتَ ".
also referenced under: Book 51, Hadith 43 (In-Book) & Volume 3, Book 47, Hadith 781 (USC-MSA)