Whenever one claims to be carrying out a critique of 'metaphysico-religious' absolutes, one has in mind the critique of onto-theology insofar as the latter coincides with the critique of Judaeo-Christian theology's claim that its belief in a unique God is founded upon supposedly rational truths, all of which are anchored in the idea of a supreme being who is the prime mover of all things. But it is necessary to point out something which, curiously enough, is not, or is no longer, self-evident. This is the fact that in criticizing metaphysics' pretension to think the absolute, we may - as indeed proved to be the case - succeed in undermining a particular religion which appealed to 'natural reason' in order to declare the superiority of its particular beliefs over those of other religions.
Thus, for example, by destroying every form of proof for the existence of a supreme being, one removes the rational support which a specific monotheistic religion invoked against every form of polytheistic religion. Consequently, by destroying metaphysics, one has effectively rendered it impossible for a particular religion to use a pseudo-rational argumentation against every other religion. But in doing so - and this is the decisive point - one has inadvertently justified belief's claim to be the only means of access to the absolute. Once the absolute has become unthinkable, even atheism, which also targets God's inexistence in the manner of an absolute, is reduced to a mere belief, and hence to a religion, albeit of the nihilist kind. Faith is pitched against faith, since what determines our fundamental choices cannot be rationally proved. In other words, the de-absolutization of thought boils down to the mobilization of a fideist argument; but a fideism that is 'fundamenal' rather than merely 'historical' in nature - that is to say, a fideism that has become thought's defence of religiosity in general, rather than of a specific religion.
... it is our conviction that the contemporary end of metaphysics is nothing other than the victory of such a fideism.Quentin Meillassoux, After Finitude: An Essay on the Necessity of Contingency (Continuum International Publishing Group, 2010), 46.