We know that God's grace is abundant and that we are completely forgiven. We trust that our salvation is eternally secure. So what keeps us from sinning? Can we now just do whatever we please and use God's forgiveness as an excuse?
Is eternal security a license to sin?
Paul answers this question in Romans 6:1-2: "What shall we say then? Are we to continue in sin that grace may abound? By no means! How can we who died to sin still live in it?" We are no longer bound to sin (Romans 6:6-7). In fact, we are now bound to Christ. Romans 6:16-18 explains, "Do you not know that if you present yourselves to anyone as obedient slaves, you are slaves of the one whom you obey, either of sin, which leads to death, or of obedience, which leads to righteousness? But thanks be to God, that you who were once slaves of sin have become obedient from the heart to the standard of teaching to which you were committed, and, having been set free from sin, have become slaves of righteousness." As believers we have been made new in Christ (2 Corinthians 5:17). While we still struggle with sin and temptation in this life, we also carry a status of righteousness in the eyes of God (2 Corinthians 5:21). We do not belong to sin but to righteousness. To use eternal security as a license to sin would be to deny who we are in Christ.
Not only does sin go against the grain of who we are in Christ, sin results in death (Romans 6:16, 23). While sin will not result in the eternal death of believers, it still has negative consequences. For believers, sin leads to distance in our relationship with God. Our eternal security is not threatened when we sin, nor is God's love for us. However, our intimacy with God is threatened. When we sin against Him, we experience the symptoms of spiritual death (such as discouragement, confusion, loneliness, and the like).
Perhaps the most compelling reason to avoid sin is God's love for us. John tells us that we love God as a result of God's love for us (1 John 4:19). Jesus said that if we love Him, we will obey Him (John 14:15). It is because we trust in God's love for us and trust that He is for our good that we also trust His commands. We know that in obeying Christ we find life. He does not ask us to do things or to refrain from doing things to boost His ego. His commands are for our benefit. Knowing that these come from God's love, and motivated by the love we feel in return, we desire to obey.
Is it possible for a Christian to lose salvation?
Is salvation by faith or works or both?
The consequences of sin - What are they?
Does my private, personal sin affect others?
What is sanctification?
Truth about Salvation