Sahih al-Bukhari, Volume 3, Book 34, Hadith 320 (USC-MSA) ⓘ
Narrated Ibn `Umar: The Prophet said, "The buyer and the seller have the option to cancel or confirm the bargain before they separate from each other or if the sale is optional." Nafi` said, "Ibn `Umar used to separate quickly from the seller if he had bought a thing which he liked."
حَدَّثَنَا صَدَقَةُ، أَخْبَرَنَا عَبْدُ الْوَهَّابِ، قَالَ سَمِعْتُ يَحْيَى، قَالَ سَمِعْتُ نَافِعًا، عَنِ ابْنِ عُمَرَ، رضى الله عنهما عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " إِنَّ الْمُتَبَايِعَيْنِ بِالْخِيَارِ فِي بَيْعِهِمَا، مَا لَمْ يَتَفَرَّقَا، أَوْ يَكُونُ الْبَيْعُ خِيَارًا " . قَالَ نَافِعٌ وَكَانَ ابْنُ عُمَرَ إِذَا اشْتَرَى شَيْئًا يُعْجِبُهُ فَارَقَ صَاحِبَهُ.
also referenced under: Book 34, Hadith 60 (In-Book) & Hadith 2107 (DarusSalam)