Perhaps the most contested book in the Jacobean period was the Book of Common Prayer. The polemic over the Prayer Book, on the part of both critics and defenders, was for the most part a continuation of that from the Elizabethan era, but two developments significantly changed the context of that polemic: a new, higher esteem for the Prayer Book from a generation whose religious sensibilities had been formed by it, and concern on the part of the episcopate with the behaviour of the laity during divine service. Taken together, these developments meant that the Prayer Book was not only being defended, but exalted, and lay conformity to its rubrics actively promoted. At the same time, it was beginning to be argued that the ritual actions required by those rubrics could not only express, but actually produce religious attitudes. As a result, the religion of the established church became more firmly, and much more consciously, what Judith Maltby has called ‘Prayer-Book Protestantism.’1 Moreover, the bishops’ focus on the performance of the liturgy, and in particular the actions of the laity, paved the way for the more radical attempt to redefine English religious identity through ‘Prayer Book performance’ under Charles I.