While it may be difficult to isolate a single "key" to victory when struggling with sin, the Scriptures are certainly not silent on the subject. One key which may be said to contain all others is found in Galatians 5:16, in which the apostle Paul tells us, "But I say, walk by the Spirit, and you will not gratify the desires of the flesh." The Spirit is the Spirit of God and the desires of the flesh are the desires of our sinful nature. Now, before explaining what it means to walk by the Spirit, we must make it clear that walking by the Spirit is an activity exclusive to those who have been saved by Christ. A non-Christian cannot walk by the Spirit because they do not possess the Holy Spirit and do not understand the things of the Spirit (1 Corinthians 2:14). Only those who believe that Jesus is the Christ are born of the Spirit, sealed by the Spirit, and indwelt by the Spirit (John 3:1–15; Ephesians 1:13–14; Romans 8:9). We are not saved by overcoming our sin in our own strength, something which is impossible to do. We are saved by Jesus' payment for our sin, which we receive through faith (Ephesians 2:8–9). Out of gratitude and love, we then fight against sin. Therefore, the first step to walking by the Spirit is to receive the Holy Spirit by believing in Jesus Christ.
I'm struggling with sin. What's the key to victory?
If you have yet to receive Christ, I pray you will do so now. Today is the day of salvation and we are not guaranteed tomorrow (2 Corinthians 6:2; James 4:14–15). Once you have received Christ, you will be a new creature with a new heart and new desires that will spring from the Spirit of God living in you (2 Corinthians 5:17; Ezekiel 36:26). Although sin will still reside in you, the Spirit of God will empower you to subdue sin so that it does not reign over you (Romans 6). The Spirit of God is infinitely stronger than our old sin nature, just as the Spirit is infinitely greater than the Devil (1 John 4:4). The Spirit of God in you will wage war against your old sin nature (Galatians 5:17). The key to victory over sin is to walk by the Spirit, yield to the Spirit, cooperate with the Spirit, and refrain from grieving the Spirit (Romans 6:12; 8:4; Philippians 2:12–13; Ephesians 4:30–32).
So, what does it look like to walk by the Spirit? Walking by the Spirit looks like saying "no" to ungodliness (Titus 2:12) and refusing to participate in the works of the flesh (sin nature), which are described in Galatians 5:19–21. Although no Christian will be perfect in this struggle against sin this side of heaven, we are empowered by the Spirit to wage war against, and progressively mortify, the sin nature (Romans 8:13). This process is called sanctification, whereby the Spirit of God gradually conforms the believer in Christ to His likeness (Romans 8:29). The evidence of this process can be seen as a Christian increasingly demonstrates the "fruit" of the Spirit listed in Galatians 5:22–23, namely: love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, and self-control.
Finally, to walk by the Spirit, and therefore have victory over sin, we must concern ourselves with the same things as the Spirit. The Spirit is chiefly concerned with honoring and bringing glory to Christ (John 16:7–15). To be successful over sin, we must treasure and love Christ above all else (Matthew 13:45–46; 19:21–22; Luke 14:25–27). The Spirit of God also is concerned with prayer. The Spirit prays for us with groanings too deep for words (Romans 8:26). Likewise, if we are to be successful over sin, we must be people who pray (1 Thessalonians 5:17). The Spirit of God teaches and illuminates the Word of God to the minds of men and women (John 14:26; 1 Corinthians 2:10; Ephesians 1:17–18). As such, we must be diligent in our study and application of the Word (2 Timothy 2:15; James 1:22). The Spirit of God is concerned about the lost and therefore we must be partners with Him in the ministry of reconciliation, by spreading the good news about Jesus Christ (Mark 16:15; 2 Corinthians 5:18). Finally, the Spirit of God is concerned with building up the church and therefore we must be busily engaged in both fellowship (Acts 2:42) and serving the needs of the church with the gifts the Spirit has given to us (1 Corinthians 12).
It is important to recognize that we cannot overcome sin on our own and we will continue to struggle with sin throughout our lifetimes. The apostle Paul wrote in Romans 7:21—8:2, "So I find it to be a law that when I want to do right, evil lies close at hand. For I delight in the law of God, in my inner being, but I see in my members another law waging war against the law of my mind and making me captive to the law of sin that dwells in my members. Wretched man that I am! Who will deliver me from this body of death? Thanks be to God through Jesus Christ our Lord! So then, I myself serve the law of God with my mind, but with my flesh I serve the law of sin. There is therefore now no condemnation for those who are in Christ Jesus. For the law of the Spirit of life has set you free in Christ Jesus from the law of sin and death." John reassures us that "if anyone does sin, we have an advocate with the Father, Jesus Christ the righteous" (1 John 2:1). The battle against sin is real. But we are counted righteous in Christ and God is at work in us to help us live righteously. We can experience victory over sin in our daily lives when we walk by the Spirit.
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