بُلُوغُ الْمَرَامِ
Bulugh al-Maram 798
Business Transactions
وَعَنْهُ: أَنَّ رَسُولَ اَللَّهِ - صلى الله عليه وسلم -قَالَ: { مَنِ اِشْتَرَى طَعَاماً فَلَا يَبِعْهُ حَتَّى يَكْتَالَهُ } رَوَاهُ مُسْلِمٌ [1] .
Narrated [Abu Hurairah (RA)]: Allah's Messenger (ﷺ) said: "If anyone buys a grain he must not sell it till he weighs it." [Reported by Muslim].
Sunnah.com reference: Book 7, Hadith 21