No religious institution or manager thereof shall allow the entry of any arms or ammunition or of any person carrying any arms or ammunition into the religious institution:

   Provided that nothing in this section shall apply to—

   (a)  the wearing and carrying of a Kirpan by any person professing the Sikh religion; or

   (b)  any arms which are used, as part of any religious ceremony or ritual of the institution as established by custom or usage.