(43) باب إِذَا لَمْ يُوَقِّتْ فِي الْخِيَارِ، هَلْ يَجُوزُ الْبَيْعُ
Narrated Ibn `Umar:
Allah's Messenger (ﷺ) said, "The seller and the buyer have the option of canceling or confirming the deal unless they separate, or one of them says to the other, 'Choose (i.e. decide to cancel or confirm the bargain now)." Perhaps he said, 'Or if it is an optional sale.' " Ibn `Umar, Shuraih, Ash-Shu`bi, Tawus, Ata, and Ibn Abu Mulaika agree upon this judgment.
Reference: Sahih al-Bukhari 2109
In-book reference: Book 34, Hadith 62
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 3, Book 34, Hadith 322