[irishsultan]

It doesn't specify a religion only in a very narrow sense. It rules out atheism as invalid, it rules out polytheistic religions (singular god).

Stating that somethings is the case does not make it so. The very article you link to states that it was intended to merge Christianity and patriotism, if you can't see how that makes it very much specific to a particular religion (although not specific to a specific church), then I don't see what evidence could convince you.