Musannaf Ibn Abi Shaybah

Hazrat Hani bin Kulthum Al-Kinani narrates that I was the commander of the army which conquered the land of Syria. I wrote to Hazrat Umar (may Allah be pleased with him) informing him that we have conquered a land in which there is abundance of food, drink, and fodder. I dislike to take any initiative regarding anything without your permission and command without your permission and command, so please write your opinion and inform us. Hazrat Umar (may Allah be pleased with him) wrote back to me, saying: Give people permission to eat and to feed their animals with fodder, and whoever sells anything in exchange for gold or silver, then on that there is khums and the Muslims' share as well.