Sahih Bukhari | Volume 3 | Hadith Number 452
Narrated by Abu Al-Bakhtari
I asked Ibn 'Umar about Salam for dates. Ibn 'Umar replied, "The Prophet forbade the sale (the fruits) of date-palms until they were fit for eating and also forbade the sale of silver for gold on credit." I also asked Ibn 'Abbas about it. Ibn 'Abbas replied, "The Prophet forbade the sale of dates till they were fit for eating, and could be weighed." I asked him, "What is to be weighed (as the dates are on the trees)?" A man sitting by Ibn 'Abbas said, "It means till they are cut and stored."