Sunan Abi Dawud, Hadith 3451 ⓘ
Narrated Yahya b. Ayyub: When Abu Zur'ah made a business transaction with a man, he gave him the right of option. He then would tell him: Give me the right of option (to annul the bargain). He said: I heard AbuHurayrah say: The Messenger of Allah said: Two people must separate only by mutual consent.
حَدَّثَنَا مُحَمَّدُ بْنُ حَاتِمٍ الْجَرْجَرَائِيُّ، قَالَ مَرْوَانُ الْفَزَارِيُّ أَخْبَرَنَا عَنْ يَحْيَى بْنِ أَيُّوبَ، قَالَ كَانَ أَبُو زُرْعَةَ إِذَا بَايَعَ رَجُلاً خَيَّرَهُ قَالَ ثُمَّ يَقُولُ خَيِّرْنِي وَيَقُولُ سَمِعْتُ أَبَا هُرَيْرَةَ يَقُولُ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " لاَ يَفْتَرِقَنَّ اثْنَانِ إِلاَّ عَنْ تَرَاضٍ " .
also referenced under: Hadith 3458 (DarusSalam) & Book 23, Hadith 3451 (USC-MSA)