Restrictions on the types of occupations that Jewish people could hold were imposed by Christian authorities. Local rulers and church officials closed many professions to religious Jews, pushing them into marginal roles that were considered socially inferior, such as tax and rent collecting and moneylending, occupations that were only tolerated as a "necessary evil". The number of Jews who were permitted to reside in different places was limited; they were concentrated in ghettos and banned from owning land. In Saudi Arabia, non-Muslims are not allowed to publicly practice their religions and they cannot enter Mecca and Medina. Furthermore, private non-Muslim religious gatherings might be raided by the religious police.