atives , ▁the ▁Roman ▁tax ▁collect ors , ▁and ▁the ▁administr ators ▁in ▁office . ▁The ▁tax es ▁to ▁the ▁central ▁government ▁were ▁calculated ▁and ▁negoti ated ▁by ▁the ▁people ' s ▁political ▁represent atives . ▁Both ▁the ▁central ▁and ▁local ▁govern ments ▁were ▁compens ated ▁for ▁the ▁services ▁each ▁provided . ▁Many ▁Christian ▁cities ▁used ▁some ▁of ▁the ▁tax es ▁to ▁maintain ▁their ▁churches ▁and ▁run ▁their ▁own ▁organizations . ▁Later , ▁the ▁Um ay y ads ▁were ▁critic ized ▁by ▁some ▁Muslim s ▁for ▁not ▁reducing ▁the ▁tax es ▁of ▁the ▁people ▁who ▁converted ▁to ▁Islam . ▁ ▁Later , ▁when ▁U mar ▁ibn ▁Abd ▁al - Az iz ▁came ▁to ▁power , ▁he ▁reduced ▁these ▁tax es . ▁He ▁is ▁therefore ▁pra ised ▁as ▁one ▁of ▁the ▁greatest ▁Muslim ▁r ul ers ▁after ▁the ▁four ▁Right ly ▁Gu ided ▁C ali ph s . ▁Im am ▁Ab u ▁Muhammad ▁Ad bul lah ▁ibn ▁Abd ul ▁H ak am ▁who ▁lived ▁in ▁ 8 2 9 ▁and ▁wrote ▁a ▁bi ography ▁on ▁U mar ▁I bn ▁Ad bul ▁Az iz ▁stated ▁that ▁the ▁reduction ▁in ▁these ▁tax es ▁stim ulated ▁the ▁economy ▁and ▁created ▁wealth ▁but ▁it ▁also ▁reduced ▁the ▁government ' s ▁budget , ▁including , ▁eventually , ▁the ▁defence ▁budget . ▁ ▁The ▁only ▁Um ay y ad ▁r uler , ▁who ▁is ▁un anim ously ▁pra ised ▁by ▁Sun ni ▁sources ▁for ▁his ▁dev out ▁p iety ▁and ▁justice ▁is ▁U mar ▁ibn ▁Abd ▁al - Az iz