Why did Locke exclude Catholics and atheists from toleration? Not, I contend, because he was trapped by his context, but because his prudential approach and practical judgments led him to traditional texts. I make this argument first by outlining the connections among prudential exceptionality, practical judgments, and traditional texts. I then describe important continuities between conventional English understandings of the relationship between state and religion and Locke's writings on toleration, discuss Locke's conception of rights, and illustrate his use of prudential exceptions and distinctions. I conclude by arguing that Locke's problems are relevant to assessing contemporary liberal discussions of toleration and the separation of state and religion that lean heavily on practical justifications.