Leslie's detailed study of the views of John Owen (1616–83) on the authority of Scripture focuses on the nature of Scripture and how Scripture's authority intersects with the life of faith. This leads Leslie to deal with a number of matters, trying to put Owen's writings in their seventeenth-century intellectual context. Issues of the ‘Scripture principle’, faith and reason, certainty, the ‘light of nature’, the habit of grace, imago Dei and the inspiration and perspicuity of Scripture are all explored here. Leslie leans heavily on Owen's The reason of faith (1677) which he sees as a refinement of Owen's earlier views. This work was part of Owen's massive five-volume study of the Holy Spirit. In brief, as Leslie says, Owen wanted to provide ‘a theological and pastoral defence of the proper means and grounds whereupon someone becomes convinced the Bible truly is the Word of God’ (p. 32). Owen wants to rest the conviction of Scripture as God's Word on God and the supernatural revelation of truth, rather than on natural human efforts or forms of rational inquiry. Leslie recognises the influence of Aquinas on Owen, especially in areas of grace and soteriology – an influence which is ‘probably true of many Reformed thinkers’ (pp. 33–4). What emerges is Owen's desire to rest recognition of Scripture's divine authority on the illumination or ‘internal witness (testimony) of the Holy Spirit’ – which is what Calvin emphasised. Yet, in Owen's context, he was ‘sensitive to the charges of irrationalism and subjectivism’ (p. 250). This led Owen to argue for grounding ‘a believer's infallible assurance of Scripture's authority in a unique kind of objective evidence that is communicated “in and by” the inspired text itself. For Owen, no less than his apologist contemporaries, the certainty of faith's adherence must merge with a certainty of evidence’ (p. 250). Again, says Leslie, ‘such an illumination is not so much an irresistible secret persuasion or internal afflatus, but a habitual impression of the Word itself upon the mind’ (p. 252). This, Leslie acknowledges, is a reframing of the Reformed doctrine of the witness of the Spirit, which had been ‘so crucial to Reformed accounts of scriptural authority, along recognizably Thomist lines, where this spiritual light is intimately associated with a new habit, infused into the soul by grace’. This, Owen calls the ‘habit of grace’ which Leslie sees as ‘a single supernatural principle or ‘quality’ which does not simply illuminate the mind, but restores the will and affections to the spiritual good under the direction of this new light, enabling them to adhere to their proper objects with faith, love, and obedience’ (p. 252). In this study, Leslie lays out fully the complexities of Owen's views, touching as they do on a number of important theological assumptions and themes. He interacts throughout with others who have studied Owen, making this book an important contribution.