Answer:
Oxford University isn't a 'religious' University as such, but it does teach theology, the study of religions, amongst other degree courses. Also, it has Permament Private Halls - essentially, halls of religious foundation, which were initially founded to house a small community of undergraduates and postgraduates who ultimately wished to become ministers, but several accept students of any religious background.
Historically a religious background was required to be a member. From the Reformation to 1870, only Anglicans were admitted. Many of the colleges have their own chapels and churches.