[T]he strictures of religion can paradoxically make you fruitful, but not if they are so strict or rigorous—so orthodox—that you become a pill. Not if you can’t take a joke, about your religion or about anything else. Not if you become so uptight that you can’t abide profanity, heresy, or apostasy.
If your religion prohibits you from using profane words, it might make you more creative, because you have to find fresher and better ways to say what you are trying to say, rather than falling back on hackneyed profanities. But if your religion has so straitjacketed your thought that you can’t even think profane thoughts, then of course it has made you less creative. One might almost say that a huge part of creativity involves lusting in your heart, then finding ways to make art of that lust; but if some brand of orthodox religiosity has worked you over too well, and you can’t even admit your heart-lust to yourself, then as an artist you are probably screwed.