Musannaf Ibn Abi Shaybah 10891 — The Christians of Banu Taghlib: what

Ubaydullah bin Abdullah said: Sayyiduna Umar (may Allah be pleased with him) appointed my father and another man as agents to collect the charities (tithes and the like) from the dhimmis who had moved to various cities and traded there. He ordered us to take half of a tenth from wheat, as a lightening for them, so that they would carry it to the city, and to take a tenth from pulses and the like.