“When our Lord and Master Jesus Christ said ‘Repent’ [Mark 1:15], he willed the entire life of believers to be one of repentance.”
That’s what Martin Luther wrote in the first of his 95 Theses that were nailed to the door at Wittenburg. The truth that Martin Luther uncovered and so aptly articulated is remarkably practical. He suggested that the Christian life is a lifestyle of faith and repentance rather than a one-time activity. At first that seems contradictory when one considers that Christ died “once for all” and put an end to sin (1 Pet. 3:18). While His work is a one-time activity that was completely finished upon the Cross, our growth in grace is not a singular experience. Transformation takes place from “one degree of glory to another” (2 Cor. 3:18).
I cannot say that I have always understood the necessity of perpetual faith and repentance in the life of the believer, and even now I struggle to effectively embrace it as a consistent practice. However, the Lord has continually opened my eyes to see the functional centrality of the gospel for daily living. What I profess to believe (the necessity of the gospel) should shape my daily practice (sanctification). The gospel is not only necessary for my deliverance from sin, but it is essential (and fully sufficient) for my growth in godliness. The grace that saves us also sanctifies us. As we repent and believe in order to gain deliverance from destruction, so we also repent and believe to gain daily deliverance from the powerful presence of sin. The penalty has been removed, but its powerful presence is only progressively eradicated. Our freedom from sin comes as the Holy Spirit applies the sin-defeating power of Christ to our lives.
As the Holy Spirit convicts us of sin, He gives us the grace to turn from our sin (repent) and put our faith in the power of the gospel. As God shows us the depth of our own depravity, we find refuge at the foot of the Cross. There is mercy and grace in the person of Christ and the work that He accomplished for us. Through such provision, we are given the ability to deny ourselves and daily take up our crosses as we follow Him (Lk. 9:22-27). Following Christ requires the daily crucifixion of our sinful hearts (Gal. 2:20; Col. 3:5; 1 Jn. 2:15-16) in order to bring about the death of all that is earthly within us. Growing in Christ means starving the sinful lusts of the flesh, lusts of the eyes, and the pride of life that wages war with the Spirit (1 Jn. 2:16; Gal. 5:17). While the Spirit shall win the war, we often lose many battles along the way. All the more reason for us to repent and believe, for that is how the Spirit delivers grace into our lives as He works sin out. Everyone who experiences the war knows that it’s terribly difficult to experience victory. Yet, the gospel promises us the power of success.
As we repent of our sin and put our faith in the gospel, we experience its deliverance (Rom. 1:16). Most believers know these truths theoretically, but living them out practically is an entirely different–and difficult–thing. However, it is refreshing for us to know that He who began a good work in us will bring it to completion at the day of Jesus Christ (Phil. 1:6). He will do the work, but we are to work out our salvation with fear and trembling. Change is never easy, but grace makes it possible. The Holy Spirit supplies the grace necessary to make my continual faith and repentance possible, and without it I lack the transforming power of the gospel. After all, God works in us both the willing and doing of His good pleasure (Phil. 2:12-13). He does this through our humble dependence that is most clearly demonstrated through a lifestyle of faith and repentance.
A helpful article for further reading: “True Spirituality: The Transforming Power of the Gospel” by Steve Childers.
Blessings in Christ, Gabe
 Martin Luther, “Ninety-Five Theses.” C.M. Jacobs, trans. Luther’s Works. Helmut T. Lehmann, gen. ed., vol. 31. (Philadelphia: Muhlenberg Press, 1957), 25-33.