The 1641 Lords’ sub-committee on religious innovation has never been the focus of a dedicated study, despite its acknowledged significance. This article presents the sub-committee as an attempt to control parliamentary discussion of the Church. Its membership was carefully selected to ensure that it would have an anti-Arminian bias. Its discussions addressed a wide range of doctrinal and liturgical questions. The Conformist members of the sub-committee were attempting to re-assert the Reformed identity of the English Church, and roll back the doctrinal and liturgical developments of the 1630s. However, despite the political crisis, they were not prepared to give much ground to Puritan opinion. The sub-committee therefore illustrates the strength of commitment, even amongst leading Reformed theologians, to the idiosyncratic aspects of the English Church Settlement. It is therefore a significant witness to the development of English Conformist opinion.