IN THE LAST nine months, John Patrick Shanley has had three plays on and off Broadway: revivals of “Doubt” and “Danny and the Deep Blue Sea,” and the debut of “Brooklyn Laundry.” While the timing is completely coincidental, the three plays cover much of his career: “Danny” premiered more than 40 years ago, and “Doubt” recently turned 20.

Despite the decades between them, these plays share a surprisingly consistent take on faith. Though raised Catholic, today Shanley demurs from identifying with any one religion. In a recent interview he told me, “It’s like when you’re among theists, you get handed a piano with 88 keys and told you can only use 13. I think that human spiritual experience is first of all mysterious and second of all, extremely rich and varied. Any reduction is just that, a subtraction from the breathtaking panoply available to us through the history of the spirit.”

In “Danny,” “Doubt,” and “Brooklyn,” God is not a comfort. Instead, Shanley’s characters are confronted with the radical, unavoidable uncertainty of reality — and challenged to go forward anyway. For Shanley, the whole idea of faith demands stripping away anything sentimental or reassuring. It isn’t faith if it isn’t well and truly a leap.