Terry Eagleton seems to have gone off on a bit of a Karen Armstrong. Interviewed by Monthly Review, here's how he answers one of the questions put to him:
You say he [Dawkins] emphasizes a "propositional" account of religious faith above a "performative" one. But how far can one go believing in God performatively, through political acts, before it becomes a proposition?
TE: All performatives imply propositions. There's no point in my operating a performative like, say, promising, or cursing, unless I have certain beliefs about the nature of reality: that there is indeed such an institution as promising, that I am able to perform it, and so on. The performative and the propositional work into each other. But it is a typically positivist kind of mistake to begin with the propositional, just as it would be for someone trying to analyze a literary text, which is basically a performance. Somebody who didn't grasp that would be making a root-and-branch mistake about the kind of thing being confronted. These new atheists, and, indeed, the great majority of believers, have been conned rather falsely into a positivist or dogmatic theology, into believing that religion consists in signing on for a set of propositions.
Everything in this confused answer hinges on the words 'begin with'. There are propositions, Terry grants, implied by religion's performatives, but we mustn't begin from them. OK, so let's not. Let's first take in everything about the performatives: that they satisfy needs for ritual, for wonder, for belonging, for consolation or whatever else. But, even then, not at the beginning but at the end, some of the propositions implied by these performatives can't be rationally defended. And for some of us that undermines the performatives. The practice of religion won't do the things for us that it does for those who believe in the implied propositions (concerning, for example, the existence of a divine and omnipotent intelligence); and therefore, whether we begin or end with this, the whole is left exactly where it was. Terry is right to say, as he does further on in the interview, that 'It is a rationalist error to think that your opponents are simply stupid.' But he's wrong to deny 'that religion consists in signing on for a set of propositions'. That may not be all religion is about, but it is, centrally, about that.