indexAimee Byrd, Theological Fitness: Why We Need a Fighting Faith (Phillipsburg, NJ: P&R Publishing, 2015). 188pgs., ppb.

Co-host of the popular Mortification of Spin podcast (with Carl Trueman and Todd Pruitt) and author of Housewife Theologian (P&R, 2013), Aimee Byrd employs the biblical metaphors of physical fitness—integrating them with her own love for being fit—into an expose of Hebrews 10:23: “Let us hold fast the confession of our hope without wavering, for he who promised is faithful.”

Aimee is described as an “ordinary mom of three,” but she’s also been a martial arts student, coffee shop owner, and Bible study teacher. She also blogs at the Alliance of Confessing Evangelical’s webpage, Housewife Theologian (alliancenet.org). In the Foreword, Carl Trueman writes,

Aimee is not a theological brain on a stick. She is a wife and a mother. She is also a fitness fanatic, and in this book she uses the notion of fitness and physical training as a theme for exploring what it means to be a vibrant, theologically aware Christian.

The “fighting grace” that Aimee explores is one that frees us to hold fast to the confession of our hope.

Theological Fitness is a fast-paced, biblically-focused, and rather humorous plea to embrace a serious study of theology as part of our perseverance in the Christian life. To “hold fast,” as the Hebrews text states, implies our utmost strength and constant perseverance to cling to our confession of faith. As Aimee writes, “Theological fitness, then, refers to the persistent fight to exercise our faith by actively engaging in the gospel truth revealed in God’s Word” (pg. 16).

But before you think she’s advocating a legalistic, moralistic approach to perseverance, it’s important to note that the book is saturated by the gospel of grace. She explains, “Only Jesus had the fitness for the work of our salvation” (Pg. 17). It’s not “You can do it; God can help,” but “God has done it; you are freed.” While Jesus is certainly an example of patient endurance, he’s not only our example. He’s our Savior and Lord. She writes, “Quite clearly, none of us could even begin to run [the race of faith] if it were not for the author and finisher of our faith. Not one of us has the fitness required to bear the curse of the world’s sin on that tree” (pg. 80). In this vein, Mrs. Byrd ably shows the connection between theological health and a growing, persevering Christian life. They are inseparable.

The book breaks down Hebrews 10:23 into five parts, each with two chapters. As she unpacks each part, she’s careful not to read into the text her own presuppositions (as best as she is able). Rather, she intentionally supports her instruction and application from the text and the surrounding context. Helpfully, too, each chapter includes a set of discussion questions that can be used for either individual or group study.

Theological Fitness also offers an impressive breadth and depth of trusted pastoral insights, from both past and present voices. From the Reformers (e.g., John Calvin), to the Puritans (e.g., Jeremiah Burroughs, John Owen, Richard Sibbes, etc.), to nineteenth-century pastors (e.g., Charles Spurgeon) to modern-day teachers and scholars (e.g., A.W. Pink, Richard Phillips, Michael Horton, G.K. Beale, Mark Jones, Derek Thomas, Kevin DeYoung, Joel Beeke, etc.), Aimee shows that her exhortations haven’t just “come to her” in a dream. They are built upon the solid biblical exposition squarely within the Reformed tradition. [NOTE: She also doesn’t mind quoting from those outside of this stream (e.g., she opens the book with a quote by Bruce Lee!).]

Aimee’s main premise—“that what we know about God, our theology, affects our Christian walk” (pg. 92)—becomes increasingly clear as the reader moves through her exposition of the Hebrews text. If we desire a healthy Christian walk—as I’m sure we would all admit—then we need to avail ourselves to the discipline of study of God’s Word and the application of that study to every area of our lives. God is faithful to finish what he began (Phil. 1:6). His work in us is a work by him. We can embrace the hope of finishing the race not because of our goodness or righteousness, but because of his grace and effectual promises.

I commend Theological Fitness as a well-researched, helpful, and practical guide to persevere in the Christian life, “for he who promised is faithful.”