Abdullah bin Masud sold some of the state's slaves to Ashath bin Qays, and they disagreed over the price.Ibn Masud said, "I sold them to you for twenty thousand."Ashath bin Qays said, "I only bought them from you for ten thousand."Abdullah said, "If you wish, I can tell you a hadith I heard from the Messenger of Allah ﷺ."Ashath said, "Go ahead."Abdullah said, "I heard the Messenger of Allah ﷺ say, 'When the two parties to a sale disagree and there is no evidence between them, while the merchandise itself remains intact, the word is the seller's, or they cancel the sale.' I therefore see that the sale should be cancelled."So he cancelled it.
حدثنا عثمان بن أبي شيبة ومحمد بن الصباح قالا حدثنا هشيم أنبأنا ابن أبي ليلى
أن عبد الله بن مسعود باع من الأشعث بن قيس رقيقا من رقيق الإمارة فاختلفا في الثمن فقال ابن مسعود بعتك بعشرين ألفا وقال الأشعث بن قيس إنما اشتريت منك بعشرة آلاف فقال عبد الله إن شئت حدثتك بحديث سمعته من رسول الله ﷺ فقال هاته قال فإني سمعت رسول الله ﷺ يقول إذا اختلف البيعان وليس بينهما بينة والبيع قائم بعينه فالقول ما قال البائع أو يترادان البيع قال فإني أرى أن أرد البيع فرده
[Hasan] Abu Dawud narrated it in the Book of Business Transactions, chapter "When the Two Parties to a Sale Disagree and the Sold Item Still Exists," hadith 3512, from the hadith of Hushaym, with this wording.Muhammad bin Abu Layla was not the only one to narrate it, as mentioned previously, hadith 854. Umar bin Qays Masir followed him (Daraqutni 2203), among others, and Ibn Jarud graded it sahih, hadith 624, as did others.