“…he who started a good work in you will carry it on to completion until the day of Christ Jesus.” (Philippians 1:6, CSB)
If God began the good work of salvation, and if He has promised to finish it, then how does He carry out that work in the meantime? Paul gives us the answer throughout his letters: God gave us His Spirit. At the moment of your conversion, you were set apart, your sins were forgiven, and your status before God changed forever. But that was only the beginning. The Christian life is not just about being saved—it is about being transformed. The Spirit of God is the one who makes that possible.
From the beginning, God’s call has been clear: “Be holy, because I am holy” (1 Peter 1:16, CSB). Holiness is not an optional extra for especially devoted Christians; it is the calling of everyone who belongs to Christ. Paul describes it this way: “So then, dear friends, since we have these promises, let us cleanse ourselves from every impurity of the flesh and spirit, bringing holiness to completion in the fear of God” (2 Corinthians 7:1, CSB). The problem, of course, is that we are weak. We live in bodies where temptation still pulls hard. Even after conversion, sin remains a struggle. That is why God gave us His Spirit—not as a symbol, but as real power for the life He commands.
Sanctification, the process of becoming holy, is not something that happens in an instant. It is a lifetime journey, one that continues “until the day of Christ Jesus.” Paul describes it in 2 Corinthians 3:18: “We all, with unveiled faces, are looking as in a mirror at the glory of the Lord and are being transformed into the same image from glory to glory; this is from the Lord who is the Spirit.” Notice the ongoing nature of the Spirit’s work. It is not once-and-done but step-by-step, stage-by-stage, glory-to-glory. You are not yet what you should be, but you are not what you once were. God’s Spirit is changing you.
The Spirit does this work in a very specific way. He is not given to whisper new revelations beyond Scripture. Instead, He strengthens us to obey what God has already revealed in His Word. He reshapes our desires, bending our hearts toward obedience. Paul explains it in Philippians 2:12-13: “Work out your own salvation with fear and trembling. For it is God who is working in you both to will and to work according to his good purpose.” God is not only helping you do what is right; He is helping you want to do what is right. He is planting new desires where there used to be rebellion.
This changes the entire tone of obedience. Without the Spirit, obedience easily becomes a desperate attempt to earn God’s approval or to avoid His punishment. But with the Spirit, obedience becomes a joyful response to God’s love. As Jesus said, “If you love me, you will keep my commands” (John 14:15, CSB). Love becomes the strongest motive. Fear may restrain sin for a while, but only love produces lasting holiness. John makes this clear: “There is no fear in love; instead, perfect love drives out fear, because fear involves punishment. So the one who fears is not complete in love. We love because he first loved us” (1 John 4:18-19, CSB).
Grace changes our motivation. We stop asking, “What do I have to do?” and start asking, “What do I get to do to show God how much I love Him?” That shift is the Spirit’s work inside of us. He changes duty into devotion and obedience into delight. This is why Paul was so confident. He knew that God had not only forgiven sins at the start but had also placed His Spirit inside him to carry him all the way to the finish.
Day by day, the Spirit renews your heart. He strengthens your will when it is weak. He gives you new desires to hate sin and to hunger for righteousness. He empowers you to say no to what destroys and yes to what pleases God. He is the quiet, steady reason that your faith endures. Without Him, your salvation would stall out. With Him, God’s promise in Philippians 1:6 is guaranteed: the good work begun in you will not be abandoned halfway.
Take This With You
You are not left to struggle on your own. God gave you His Spirit so that the life He began in you could grow and flourish. The Spirit is the down payment of your inheritance, the power behind your obedience, and the guarantee that God’s work in you will reach completion.
