In that year (235/850), al-Mutawakkil ordered that the Christians and all the rest of the ahl al-dhimma be made to wear honey-colored taylasans (hoods) and the zunnar belts. They were to ride on saddles with wooden stirrups, and two balls were to be attached to the rear of' their saddles. fie required them to attach two buttons oil their qalansuwas (conical caps) - those of, their) that wore this cap. And it was to be of a different color from the qalansuwa worn by Muslims. He further required them to affix two patches on the exterior of then slaves' garments. The color of these patches had to be different from that of the garment. One of the patches was to be worn in front oil the breast and the other on the back. Each of the patches should measure four fingers in diameter. They too were to be honey-colored. Whosoever of them wears a turban, its color was likewise to be honeycolored. If any of their women went out veiled, they had to be enveloped in a honey-colored izar (large wrap). He further commanded that their slaves be made to wear the zunnar and be forbidden to wear the mintaqa (Arab military belt).
He gave orders that any of their houses of worship built after the advent of Islam were to be destroyed and that one-tenth of their homes be confiscated. If the place was spacious enough, it was to be converted into a mosque. If it was not suitable for a mosque, it was to be made an open space. He commanded that wooden images of devils be nailed to the doors of their homes to distinguish them from the homes of Muslims.
He forbade their being employed in the government offices or in any official business whereby they might have authority over Muslims. He prohibited their children [from] studying in Muslim schools. Nor was any Muslim permitted to teach them. He forbade them to display crosses on their Palm Sundays, and he prohibited any Jewish chanting in the streets. He gave orders that their graves should be made level with the ground so as not to resemble the graves of Muslims. And he wrote to all his governors regarding this (pp. 167-68).
al-Tabari (d. 923), Ta'rikh al-Rusul wa'l-Muluk, in N. Stillman.
Sources: Bat Ye'or, The Dhimmi. Rutherford: Fairleigh Dickinson University Press, 1985.