David L. Clough is Professor of Theological Ethics at the University of Chester in the U. K. He is also the founder of the CreatureKind a faith-based project with a focus on farmed animal welfare. Clough’s first volume, On Animals: Systematic Theology, published in 2012, is surely the most significant theological account to date of the ways human beings are related to animals. (Or as Clough often puts it, the way human animals are related to non-human animals.) Volume two, On Animals: Theological Ethics, published in 2019, is a Christian ethical analysis growing out of the theology of the first volume. The seven-year gap suggests why Clough’s work was published as two volumes when they could have and perhaps should have been published as a single volume. On Animals: Systematic Theology is biblical, historical, doctrinal and, above all, theological. After the biblical writers, Clough’s primary conversation partners are people like Augustine, Thomas, Luther, Calvin, Wesley, and Barth, as well as a host of lesser known Christian thinkers and saints. As a result, the volume is readily accessible to anyone with a basic knowledge of the Bible and the Christian theological tradition. Although Clough engages a wide range of non-theological writers, such as Aristotle and Descartes, he does not depend upon them for methodology or prolegomena. He also engages with authors who have written about human relationships to animals—such as Singer and Nussbaum—but they too play subordinate roles largely to allow his distinctive positions to emerge.
 The argument of On Animals: Systematic Theology can be brutally summarized as follows: God is gracious to all creatures, not just humans. The book of Genesis tells us that animals, human and non-human, existed peacefully in the Garden of Eden. Since the fall, humans and animals have competed, often violently, for survival. The incarnation and atoning work of Christ includes human and non-human animals, all groaning for the redemption that is so eloquently described by Paul in Romans 8. If God has created and reconciled human and non-human animals, is it not reasonable to assume that God will redeem them? Clough thinks so and his major contribution—looking at animals under doctrinal headings of creation, reconciliation, and redemption—is where his argument stands or falls. On Animals: Theological Ethics asks how Christians are to live with fellow creatures which/who are also, in their own ways, groaning for redemption. For over 200 pages, Clough considers the ways people interact with animals for food, clothing and textiles, labor, medical research and education, sport and entertainment, and as companions and pets. In each case, he asks about the extent to which common human practices and behaviors are compatible with the belief that non-human animals are included in God’s redemptive plans. Clough is not an absolutist and does not shrink from ambiguities, offering thoughtful and nuanced comments along the way. To take pets, for example, he argues that there are ways to live with animals as pets or companions that are compatible with the theological positions he articulates and there are ways that are not.
 Clough’s major ethical concern is with the use of animals and animal products for human food. Put simply, he asks under which conditions, if any, should we eat fellow creatures that will be redeemed by God? The importance of the question is heightened since, as anyone familiar with modern factory farming knows, the conditions are horrendous for the animals and those who slaughter and process them. Moreover, factory farming—including fish farming—is far more destructive to the environment than other types of food cultivation. To get at these issues, Clough cites two parallel situations: war and slavery. In a fallen world, war is sometimes necessary, though the goal of Christian people is always to minimize war, love their enemies, and do whatever is possible to eliminate the causes of war and thus war itself. This is the demand and the promise of most forms of just war theory. In a fallen world, slavery has also often been a fact. The goal of Christian people, even many Christian slave holders, was to minimize slavery and work toward the day when slavery would be no more. Similarly, in a fallen world, it has been and sometimes is necessary to eat non-human animals. But how do we live or grow into a time when animals, human and non-human alike, will share a peaceful existence in the fullness of God’s reign—not looking back to the Garden of Eden, but ahead to the new heavens and the new earth? Clough makes much of nineteenth-century Christian movements against vivisection and cruelty to animals as admirable foundations on which to build in the twenty-first century. Why did these movements not lead to a greater sensitivity to eating animal meat and products, especially by Christians, in the twentieth century? Changes in farming/food production that developed in the last hundred years or so offer one explanation. For much of human history, meat was a food for the wealthy or used sparingly by others to survive harsh winters. Animals were raised on a relatively small scale, both in terms of how they were raised—on or near family farms—and the comparatively small amount of meat and animal products that were consumed. For centuries, families spent a season feeding a pig in the back yard. They knew that in the autumn it would be slaughtered to provide food for the long winter. God would be thanked, the pig would be appreciated, and nothing would be wasted. Today, billions of people get their food from “factory farms” designed to provide massive quantities of animal meat and products at the lowest possible prices under ghastly conditions for the animals, for those who slaughter and process them, and for the environment generally. Why are factory farming practices—cramped quarters, high stress levels, debeaking, forced feeding, etc. not seen as morally troublesome as things like bullfights, foxhunts, and dog fighting? Clough’s historical sketches of human attitudes towards animals offers several explanations. Perhaps the most relevant one today is that people continue to believe they need to eat animal meat and products to be healthy and, one could add, to enjoy food. As such, people duck the facts about factory farming just as many people ducked moral issues of slavery.
 Clough is neither a dogmatist nor an ideologue. His methodology is pluralistic and his approach is pragmatic. He does not get bogged down in “what if” questions or anything else designed to take the focus off improving the ways human beings relate to animals. He wants to get his proposals about animals out there, especially to people who purport to share his basic doctrinal commitments. He is realistic in seeing no large scale or quick solutions on the horizon. Clough believes that any approximation of God’s provision for the redemption of all things is better than no approximation. He is grateful for small gains. Clough’s conclusions are open for discussion and refinement. He does not condemn those who differ from him, though there are times when the force or direction of his arguments leaves little room for different conclusions. Even so, he is patient and hopeful that his volumes will contribute to a movement away from factory farming and other practices that do not take animals seriously as objects of God’s attention and redemption.
 Readers who saw the film The Matrix will remember that Morpheus confronts Neo, a character who is gradually awakening to reality, with a choice of two pills. If Neo wants to know the truth, the blue pill will open his eyes, and his life will never be the same. If Neo takes the red pill, he will go back to his normal life and he will remain vaguely troubled but ultimately ignorant. David Clough’s On Animals is a blue pill. After reading these books, it will be much harder to duck the issues. That, Clough would say, would be a good thing—good for animals, human and otherwise, and for the world. The only bad thing about Clough’s volumes are their prices. Unfortunately, the high cost will work against the wide circulation these volumes deserve.