بُلُوغُ الْمَرَامِ
Bulugh al-Maram 836
Business Transactions
وَعَنْ جَابِرِ بْنِ عَبْدِ اَللَّهِ -رَضِيَ اَللَّهُ عَنْهُمَا- قَالَ : { نَهَى رَسُولُ اَللَّهِ - صلى الله عليه وسلم -عَنْ بَيْعِ اَلصُّبْرَةِ مِنَ اَلتَّمْرِ لا يُعْلَمُ مَكِيلُهَا [1] بِالْكَيْلِ اَلْمُسَمَّى مِنَ اَلتَّمْرِ } رَوَاهُ مُسْلِمٌ [2] .
Narrated Jabir bin 'Abdullah (RA): Allah's Messenger (ﷺ) forbade selling a quantity of dates whose measure was unknown for a specified (known) quantity of dates. [Reported by Muslim].
Sunnah.com reference: Book 7, Hadith 70