وَعَنْهُ قَالَ: نَهَى رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ عَنْ بَيْعِ الصُّبْرَةِ مِنَ التَّمْرِ لَا يُعْلَمُ مَكِيلَتُهَا بِالْكَيْلِ الْمُسَمَّى مِنَ التَّمْرِ
He said that God’s Messenger forbade selling a quantity of dates whose measure was unknown for a specific quantity of dates.
Mishkat al-Masabih 2699, Book 12, Business Transactions, Hadith 55. 1 min read