Why do groups such as Christadelphians, Jehovah's Witnesses, and Unitarians have such difficulty with the doctrine of the Trinity? Do they really understand the doctrine they oppose? From the mainstream Christian perspective, perhaps a lack of understanding about the way these other groups view the Scriptures may have hampered a clear presentation of the orthodox doctrine. The Trinity Hurdle is a scriptural and historical defense of the doctrine of the Triune God and substitutionary atonement for Christadelphians, other non-Trinitarians, and those engaging with them, from an author who is familiar with both sides of the doctrinal divide. ""I learned a lot about Christadelphian doctrines and attitudes from reading Sutcliffe's clear and helpful book, even though it was written to work the other way around: to help Christadelphians understand what Trinitarian Christians actually believe and teach. That the book can work in either direction is a testament to how well the author keeps to the main things, explaining basic theology and engaging widespread misunderstandings."" --Fred Sanders, Professor of Theology, Torrey Honors Institute, Biola University This is a carefully argued, nuanced, and much-needed book. Sutcliffe has drawn on many years' experience, searching reflection, and thorough exegesis of the Cristadelphian movement to provide us with a resource I hope will be used for many years to come."" --Gary Millar, Principal, Queensland Theological College ""This intriguing book fills a gap in the literature which few may have noticed but which is significant nonetheless. Christadelphians are not well-known and have often been overlooked, but their non-Trinitarian beliefs are more widely shared and their claims need to be considered--and answered. Sutcliffe has done an admirable job of researching the Christadelphian claims and providing the kind of response that is needed."" --Gerald Bray, Research Professor of Divinity, Beeson Divinity School ""Ruth Sutcliffe has written a unique and valuable book. If you are thinking about the differences between orthodox Christian faith and the beliefs of Christadelphians and Unitarians, you will find here the clearest, best-informed, and most sensitive explanation available. Ruth's own discovery of the gospel of grace in Trinitarian faith informs the book throughout. If you simply want to understand better why Christians believe in the Trinity and why that matters for the gospel -- The Trinity Hurdle will give you that too."" --John McClean, Vice Principal, Lecturer in Systematic Theology, Christ College Ruth Sutcliffe is a former Christadelphian who is now ""preaching the faith once denied."" She holds a Master of Divinity from the Australian College of Theology, and a Graduate Certificate in Tertiary Teaching. She teaches theology and church history in North Queensland, Australia and authors a blog, R Sutcliffe Theologistics, which complements this book.