Ja'far bin Brqan جعفر بن برقان · Commercial Transactions (Kitab Al-Buyu)

I heard the Messenger of Allah (ﷺ) say: If any of you does not leave mukhabarah, he should take notice of war from Allah and His Apostle (ﷺ).

The Prophet (ﷺ) handed over the Jews of Khaibar the palm trees and the land of Khaibar on condition that they should employ what belonged to them in working on them, and that he should have half of the fruits.

The Messenger of Allah (ﷺ) conquered Khaibar, and stipulated that all the land, gold and silver would belong to him. The people of Khaibar said: we know the land more than you ; so give it to us on condition that you should have half of the produce and we would have the half. He then gave it to them on that condition. When the time of picking the fruits of the palm-trees came, he sent 'Abd Allah b. Rawahah…

He said: He assessed, and after the words of kull safara' wa baida', he said: that is, gold and silver will belong to him.