By: Arnie Cole
What if your spiritual fitness could grow stronger as your physical body ages? While we all know that physical fitness naturally declines with time, spiritual fitness follows a different path. It’s a lifelong process of growth and transformation that continues up until the day we meet the Lord. This concept offers a powerful analogy for the Christian doctrine of sanctification—a journey of becoming more like Christ, where, unlike physical fitness, progress never has to stop.
With this analogy in mind, let’s explore the Christian doctrine of sanctification. “Sanctification” is the term Christian Bible scholars, pastors, and theologians use to describe the process by which God transforms us into the image of Christ. When we believe in Christ, and our sins are forgiven, God’s work doesn’t stop. In fact, his work has only begun.
From the moment we believe in Christ, God sets forth to make us more and more like his Son. But this doesn’t happen automatically. We have to cooperate. Just as a fitness plan requires commitment and effort, so too does the process of sanctification. God’s will for us is to be sanctified (1 Thessalonians 4:3), and this transformative journey involves every aspect of who we are.
At its core, sanctification is about holiness—becoming set apart for God’s purposes. Hebrews 12:14 reminds us to “make every effort to be holy,” which requires continual spiritual exercise. We are not called to an instantaneous change but to a progressive, often uneven, journey. Like physical fitness, which ebbs and flows depending on our circumstances, sanctification can feel like a series of victories and setbacks. Yet, through it all, God’s grace enables us to grow daily (2 Corinthians 4:16) and transform from glory to glory (2 Corinthians 3:18).
The Holistic Nature of Spiritual Fitness
While physical fitness often focuses on specific parts of the body—strengthening particular muscles or improving cardiovascular health—spiritual fitness is holistic. It touches every part of our being, from our thoughts and emotions to our actions and relationships. Romans 12:1 encourages us to offer our whole selves as living sacrifices to God, meaning that no area of life is untouched by His sanctifying power.
Think of it this way: Just as a healthy body depends on more than one exercise or diet plan, our spiritual lives depend on more than just quiet times, prayer meetings, or church attendance. Sanctification involves every area of life—our work, family, relationships, hobbies, and even our inner thoughts. As Abraham Kuyper was fond of saying, Christ’s Lordship extends over every square inch of our lives, and we are called to reflect His holiness in all we do.
In the same way that physical training requires us to break unhealthy habits, spiritual fitness calls us to break patterns of sin and adopt practices that reflect the character of Christ. This kind of transformation doesn’t just stay in the “religious” part of our lives but reaches into the artistic, scientific, educational, and even entrepreneurial aspects of who we are. In short, spiritual fitness transforms everything.
The Spirit As Our Guide and Enabler
Just as no one can become physically fit without guidance and help, we cannot become spiritually fit without the Holy Spirit’s work. He is the one who enables us to do what our sinful nature could never achieve (Romans 8:3-4). At conversion, the Holy Spirit baptizes us into the universal church (1 Corinthians 12:13) and gives us spiritual gifts to use for the glory of God (Romans 12:3-8).
The Holy Spirit is like a personal trainer, not only helping us apply the truths of Scripture to our lives but also empowering us to resist sin, speak boldly, and mature in our relationships. Through His indwelling presence (1 Corinthians 6:19-20), we are progressively transformed and sealed for the day of redemption (Ephesians 4:30).
Spiritual Fitness for the Christian Life
As we have noted, spiritual fitness differs from physical fitness in that our spiritual fitness can progress even though our body declines with age. Paul encourages us to grow in the grace and knowledge of our Lord Jesus Christ (2 Peter 3:18), reminding us that sanctification is a lifelong journey, not a one-time event. Yet, spiritual fitness is similar to physical fitness in that it is hard work, requires daily discipline, and leads to transformation. What’s more, like physical fitness, spiritual fitness is gratifying and brings tangible results.
So, let’s not frustrate God’s intentions. Let’s cooperate with him as he guides us toward becoming more like his Son. The process will sometimes be slow, uneven, or otherwise frustrating, but through it all, we are being conformed to the image of the Perfect One. And just like with physical fitness, the more we exercise our spiritual muscles, the more we become the person God has called us to be.
Let us embrace God’s desire to make us ever more spiritually fit. Casting aside apathy and the sins that so easily beset us, let us grow stronger and more mature in Christ by the grace of God and the power of the Holy Spirit. While our bodies may weaken, our souls can be continually strengthened until we reach our final day and stand perfected in His presence.