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'Advancement of religion' is one of the four categories of charitable purpose set out in Pemsels Case (1891).

The courts are neutral on the subject or religion. That is to say, they favour no particular religion over any other when it comes to the question of a trust's charitable status. A very wide assortment of religious bodies has been deemed charitable. (In this context it is important to remember, bearing in mind the anti-Mortmain provisions of the 17th century, that this may be as much to restrict the creation of religious trusts as to encourage them.)

However, there is no question that, as far as the courts are concerned, religion implies a belief in a higher spiritual being (re South Place Ethical Society 1980). Any organization promoting simply ethical standards of behaviour or a particular humanist world-view is not, in the legal sense, a 'religion'. Presumably, some movements considered significant world religions would not qualify as religions in the legal sense (e.g. certain varieties of Bhuddism perhaps). There are, of course, borderline cases. The so-called 'Church of Scientology' was denied charitable status in the UK; however, using precisely the same case-law, it was accorded this status in Australia.