Paul Lim concludes this densely researched and thoughtful exploration of Trinitarian debates in seventeenth-century England with the words of Hilary of Poitiers, rendered by Andrew Marvell in a controversial work of 1680: ‘We are now all of us torn in pieces.’ This devastating verdict on the state of early modern theology (and especially the proliferation of creeds, councils and persecutions, analogous to Hilary's own time) echoes the dismay of contemporaries, beholding in Western Christianity a broken body. Lim's analysis helps to interpret the significance of defending and renouncing the Trinity in a period of intellectual crisis and fragmentation, as he examines a broad spectrum of commentators from the theatrically antinomian to the pugnaciously Tory.

The book is essentially a collection of essays united by the theme of ‘mystery’, contributing to many discussions, both historiographical and historical-theological, along the way. Inevitably, it opens with the furore surrounding the anti-Trinitarian writings of Paul Best and John Biddle from 1647, explaining the religious and primitivist impulse that lay behind their deconstruction of Nicene orthodoxy, and rejecting firmly any secularising interpretation of their thought. In the second chapter, Lim sketches the broad radical milieu of the 1640s and '50 s which accommodated both Socinian rationalism and the ‘spiritist piety’ of the antinomian sects, suggesting that they might even be regarded as ‘ideological correlates’ in their erosion of ethical custom and theological tradition. He is keen to offer a balanced portrait of both the anti- or non-Trinitarians themselves and their critics, devoting the chapter which follows to the cross-confessional defence of the Trinity and especially the vexed status of reason and mystery among Biddle's adversaries.

Most rewarding for this reviewer was the close and sensitive reading of Francis Cheynell and John Owen in chapter iv, and the sustained argument that affective spirituality and Trinitarian apologetics were two sides of the same coin for Reformed theologians; that the contrast between practical and polemical divinity is a false one. Lim's exposition is enriched by a deep understanding of Calvin's anthropology, and casts light on the surprisingly dominant appeal to mystical, experiential union as the practical proof of the Trinity. The concluding essays deal with common scepticism in Hobbes, Baxter and Marvell concerning the reliability of councils, especially in their judgement on heresy; and with the hermeneutical issues surrounding Christology in the Gospel of John.

There are some problems: Mystery unveiled can be difficult to read, with its copious notes and syntactical infelicities. Occasionally it feels unedited, and undeveloped in argument and narrative: there is little by way of rationale for chronological scope, or for the inclusion of certain protagonists and juxtapositions, and the exclusion of others (Marvell over Milton, for instance). But Lim's book offers many lucid insights into and fresh ideas about seventeenth-century religion, and it will compensate careful study.