Musannaf Ibn Abi Shayba 13:846

Abu Bakr narrated to us, he said: Waki’ narrated to us, from Fudayl ibn Ghazwan, from ‘Abd al-Rahman ibn Hazim, from Mujahid, he said: I asked him about buying land of *kharaj* (taxable land), and he said: "Do not sell it, and do not buy it."