Saib bin Yazid (may Allah be pleased with him) says: In the time of Umar bin Khattab (may Allah be pleased with him), I was an official in the market of Madinah along with Abdullah bin Utbah. Abdullah bin Utbah used to collect ‘ushr (a type of tax) from the Nabateans.
Hadith Referenceمسند الإمام الشافعي / كتاب الزكاة / 742
Hadith Takhrijاسناده صحیح اخرجه البيهقي : 9 / 210 ۔ وفى المعرفة السنن والآثار له (5543) ۔ وعبد الرزاق (10117) ، (19279)۔