The Christian life is built upon the foundation of assurance. The Bible tells man that he is sinful and wholly incapable of doing anything whatsoever to merit God’s favor. The punishment for sin is death, eternal separation from God. But God loves us. He sent His Son into the world to bear our sins by dying on the cross. Jesus Christ did all the work to solve humanity’s sin problem and He offers all the gift of forgiveness through believing in Him. This Good News is not one that man would devise on his own, which is why we must go to God’s revelation, the Bible, to learn it. Scripture explain God’s righteousness, our sinfulness, and God’s solution through believing in the Savior’s work. Because the message comes from God we can trust it. The most straightforward passage concerning how to receive the gift of salvation is Acts 16:31 “Believe in the Lord Jesus, and you will be saved” [ESV]. Anyone who does this is saved at the moment of belief and can know for certain of his eternal destiny with God because he has trusted in a promise from God.
God puts a high value on His word: He used it to bring the universe into existence (cf. Gen. 1:3), He uses it to sustain His creation (Heb. 1:3), He sees it as more compelling testimony than even miracles (Lk. 16:31), and He places it on equal level with Himself (Ps. 138:2). We can know for certain of our salvation by trusting that what God says in His word is accurate and adequate. Because of the believer’s absolute assurance in God’s message, he can avail Himself of the many other grace provisions that make up God’s salvation package in order to live a life of holiness in obedience to God’s many commands for Christians. The good works result from complete assurance.
God gives believers many commands to follow in order to live an abundant life that glorifies Him. These commands are only for believers because faith in Christ marks the beginning of a new life in God’s family. God has extremely high expectations for His children and the more fully aware one becomes of Who God is and what Jesus did for him, the more willing he should be to rely on God’s Spirit to live a life of obedience. But obedience depends on a choice. In any scenario where we are commanded to do something, we have a choice as to whether or not we will obey. This is just as true in the Christian life as anywhere else. Failure to obey can result in consequences, but since God provides salvation from the penalty of sin on the basis of Jesus’ obedience, and since any knowledge of what Jesus did comes from the Bible, and since we appropriated the gift of forgiveness by trusting in Jesus on the basis of what God says in His word, failure to live a life of obedience cannot result in the loss of salvation; neither should it result in the loss of assurance.
Often those who proscribe that not Jesus’ work but an individual’s actions are “the basis of assurance” present scenarios such as this:
“In a well-motivated effort to magnify the free grace of God, it is possible to teach the truth of justification by faith alone through Christ alone without connecting all of the dots for our hearers. But the teaching of Scripture is that the justifying work of Christ will always produce the fruit of righteousness in the lives of believers, …(for just one example, see the logic of Romans 6:1-14).
A disconnect between justification and sanctification … is doubly dangerous for those who have false assurance, because it encourages them to think that it is possible to live in open rebellion against God and still be righteous in his sight.”
First, it is interesting to note that the logic of Romans 6:1-14 concludes with these commands: “you also must consider yourselves dead to sin and alive to God in Christ Jesus” (v. 11), “Let not sin reign in your mortal body” (v. 12), and “do not present your members to sin as instruments for unrighteousness, but present yourselves to God as instruments for righteousness” (v. 13). If the justifying work of Christ always produces righteous lives, why is Paul so adamant about commanding believers to live holy lives? Second, the assurance of the gospel is straightforward: you can know if you are saved on the basis of trusting the promises of Scripture: if you “believe in the Lord Jesus Christ,” you are saved. This article negates straightforward assurance; an individual who has never trusted in Christ for salvation would have to be told to stop living in open rebellion against God in order to be saved, but the empowering presence of the Holy Spirit received at the moment of faith in Christ enables someone to stop living rebelliously. This puts the cart before the horse, and makes sin the issue in regards to salvation instead of Jesus Christ. Furthermore, the article previously admitted that someone’s moral life can lead to false assurance because “moral lives might be the evidence of someone’s faith in the gospel.” So, on the one hand, only trusting in Christ without an emphasis on a holy life can lead to false assurance, and on the other hand, only living a moral life can lead to false assurance. How is one to know if his moral life is the right kind to ensure assurance?
God calls Christians to live a life of obedience in service to Him. We do not do it to make sure we are his children as if God wanted us to look to our own actions for proof. Instead, obedience is what should result from the assurance God provides in His word. “But to all who did receive Him, who believed in His name, He gave the right to become children of God” (Jn. 1:12). We receive Jesus Christ through believing in Who He is, and what He did. If there is any doubt, look to Jesus, then stop doubting God’s word and build your life on the absolute assurance you have from God in Jesus.
 Mike McKinley, “Six Ways to Give Your People False Assurance,” 29 February 2012. 9 Marks.