Sahih al-Bukhari 2113

Arabic

حَدَّثَنَا مُحَمَّدُ بْنُ يُوسُفَ، حَدَّثَنَا سُفْيَانُ، عَنْ عَبْدِ اللَّهِ بْنِ دِينَارٍ، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ ‏ "‏ كُلُّ بَيِّعَيْنِ لاَ بَيْعَ بَيْنَهُمَا حَتَّى يَتَفَرَّقَا، إِلاَّ بَيْعَ الْخِيَارِ ‏"‏‏.‏

English translation

Narrated Ibn `Umar:The Prophet (ﷺ) said, "No deal is settled and finalized unless the buyer and the seller separate, except if the deal is optional (whereby the validity of the bargain depends on the stipulations agreed upon)

Reference: Sahih al-Bukhari 2113, Book of Sales and Trade. English translation by Dr. Muhammad Muhsin Khan.