In his new book, “Spiritual Fitness for the Soul: Daily Habits to Energize Your Faith and Strengthen Your Walk with Christ” (Whitaker House), behavioral researcher and ministry leader Arnie Cole shows Christians how simple daily habits can strengthen their faith and lead to lasting spiritual change. While leading the Center for Bible Engagement at Back to the Bible, Cole and his research team identified a striking pattern: people who engaged with Scripture on four or more days each week reported significantly healthier behavioral and spiritual outcomes than those who engaged less often. That finding became known as the “Power of 4.”
The research found that respondents who engaged with Scripture on at least four days in a given week had 62% lower odds of drinking to excess, 59% lower odds of viewing pornography, 31% lower odds of lashing out in anger, 28% lower odds of lying, and 28% lower odds of gossiping, among other findings.
Cole says the earlier research established the importance of regularly engaging with Scripture, but it also led to another important question: What helps God’s Word move from something a person reads to something that changes the way that person thinks, lives, and relates to others?
“The earlier research showed us that frequency matters,” says Cole. “But opening the Bible is not the finish line. The goal is for God’s Word to get inside us—to shape our decisions, our relationships, our attitudes, and the way we respond to everyday life.”
“Spiritual Fitness for the Soul” explores that next step through what Cole calls Scripture Absorption.
“When we immerse ourselves in God’s Word, we do more than gain knowledge. We build spiritual resilience,” says Cole. “Spiritual fitness isn’t about doing more religious activities. It’s about doing the right things consistently. Many Christians are spiritually exhausted—not because they don’t love God, but because they have never learned how to train their souls.”
Cole says many Christians know there should be more to their spiritual lives but are unsure how to get back on track.
“We spend hours strengthening our bodies but often only minutes strengthening our faith,” says Cole. “We cannot expect spiritual strength if we are starving our souls. Spiritual growth is not built on occasional inspiration. It is built through daily habits that allow God’s Word to take root in us.”
In the book, Cole recounts how he once felt spiritually empty himself. His turning point came during a trip to Alaska, when a massive storm threatened the boat he was aboard.
Cole says he prayed what he now describes as a “foxhole prayer,” asking God to save him.
“At first, I thought I was bargaining with God,” says Cole. “I didn’t really mean the prayer. But when what looked like an 80-foot wave hit our boat and it felt as though we were going to capsize, I prayed again—and this time I meant it. That was the moment of my genuine conversion.”
Cole knew his life needed to change, but he soon discovered that knowing he needed to change and knowing how to change were two different things.
“Like many Christians, I tried self-help approaches, more discipline, and adding more religious activities to my life,” says Cole. “Nothing seemed to work. But when I began digging into Scripture, reflecting on it, and allowing it to challenge the way I lived, I began to see real transformation.”
“Spiritual Fitness for the Soul” offers readers a practical blueprint for bringing Scripture into daily life in ways Cole says are both “actionable and relational.” Cole organizes the Scripture Absorption process around four movements: Receive, Reflect, Respond, and Reveal.
“First, we Receive Scripture by reading or listening to a passage from God’s Word,” says Cole. “Then we Reflect on what it means and where it connects with our lives. Third, we Respond by turning what we have learned into a specific act of trust or obedience. Finally, we Reveal by sharing with another person what God is teaching us.”
Cole says the fourth step is especially important because he says spiritual growth was “never intended to remain private.”
“When we share what God is showing us with a family member, friend, coworker, or someone we are mentoring, it strengthens our own understanding and encourages someone else,” says Cole. “That is how Scripture moves from the page into a life—and from one life into another.”
Cole says transformation is possible, but it does not happen by accident.
“God never intended Christianity to be something we admire from a distance,” says Cole. “He intended it to transform us from the inside out. Many Christians are spiritually sincere but spiritually out of shape. The answer is not more guilt or more religious activity. The answer is learning how to receive God’s Word, absorb it, live it, and pass it on.”
In June 2023, Back to the Bible sold the Center for Bible Engagement’s intellectual property, including the “Power of 4” research, to Our Daily Bread Ministries. Cole and his research colleagues remained at Back to the Bible, where they began a new line of research focused on Scripture Absorption.
About Arnie Cole:
Arnie Cole, Ed.D., is CEO of Back to the Bible and has served as a social researcher for more than three decades. His work focuses on discipleship formation, spiritual fitness, and translating research data into practical ministry strategies for local churches and Christian media. For further information visit www.backtothebible.org.