I asked Ibn Abbas about selling palm trees, and he said, "The Messenger of Allah ﷺ forbade selling palm trees until one can eat from them or they can be eaten, and until they can be weighed."I asked, "What does 'weighed' mean?"A man who was with him replied, "Until they can be estimated."
سألت ابن عباس عن بيع النخل، فقال: نهي رسول الله ﷺ عن بيع النخل حتى يأكل منه أو يوكل، وحتى يوزن. قال: فقلت: ما يوزن؟ فقال رجل عنده حتى يحزر.
Narrated by Bukhari in the chapter on forward sale (2246), and Muslim in the chapter on sales (1537), both through the route of Shuba, Amr bin Mura informed us, he said, I heard Abu Bakhtari Tai, then he related it. The wording given is Muslim's. Bukhari's wording is similar, except that he said, I asked Ibn Abbas about forward sale contracts on date-palms. In his version it occurs as "hatta yuhraz" instead of "yuhzar."Hafiz said in Fath al-Bari (4/432), "His statement, 'hatta yuhraz,' with the ra coming before the za, means to be safeguarded and preserved. In the narration of Kashmihani, it comes with the za before the ra, meaning to be weighed or estimated by guess. He said, Iyad judged the first reading to be correct, but the second is more fitting given the mention of weighing."