Abdullah bin Umar reported,

Someone asked Ibn Abbas about paying in advance for dates on a palm tree before the fruit had appeared.He answered, "No."The questioner asked, "Why?"He explained, "A man paid in advance for the produce of a palm grove during the time of the Messenger of Allah ﷺ before the palms had borne fruit. That year the palms produced nothing. The buyer said, 'It belongs to me until the trees bear fruit,' while the seller said, 'I only sold you the produce of this year.' They brought their dispute to the Messenger of Allah ﷺ, who asked the seller, 'Did you take anything from his palm grove?' He replied, 'No.' The Prophet said, 'Then on what basis do you consider his money lawful for yourself? Return to him what you took from him.' Then he said, 'Do not pay in advance for dates on a palm tree until their soundness becomes apparent.'"

حدثنا هناد بن السري حدثنا أبو الأحوص عن أبي إسحق عن النجراني قال قلت

لعبد الله بن عمر

أسلم في نخل قبل أن يطلع قال لا قلت لم قال إن رجلا أسلم في حديقة نخل في عهد رسول الله ﷺ قبل أن يطلع النخل فلم يطلع النخل شيئا ذلك العام فقال المشتري هو لي حتى يطلع وقال البائع إنما بعتك النخل هذه السنة فاختصما إلى رسول الله ﷺ فقال للبائع أخذ من نخلك شيئا قال لا قال فبم تستحل ماله اردد عليه ما أخذت منه ولا تسلموا في نخل حتى يبدو صلاحه