No one who trusts in Jesus Christ will be eternally lost. Jesus said, “All that the Father gives to me will come to me, and whoever comes to me I will never cast out” (John 6:37). Anyone who has come to Christ belongs to Christ forever. Everyone who has faith in Christ has eternal life (John 6:40).
Yet Christians often fear that they have not really come to Christ. They want assurance that their faith is real. They want to know for sure that they are God’s children. The Bible teaches that this desire for assurance conforms to God’s will for His people. God wants believers to know that their faith is genuine. He wants them to be sure that they belong to Him and have eternal life through Christ.
Assurance of salvation is the knowledge and confidence that one belongs to Christ (1 John 5:13). Christians find assurance through many means, including their faith. In fact, the Bible defines faith as “the assurance of things hoped for” (Heb. 11:1). When the Apostle Paul described Abraham as a model of faith, he said that Abraham was “fully convinced that God was able to do what he had promised” (Rom. 4:21). Abraham knew that God would keep His promises. Abraham was sure of it.
The assurance of salvation, then, comes from trust in God, and trust entails knowing and believing God’s promises. Christian faith, like Abraham’s, believes what God says. Christians believe a particular message from God: the gospel. The gospel is the good news that Jesus Christ fulfilled the law, died for sinners, and rose to life again (1 Cor. 15:3–11). When people believe the gospel, they entrust themselves to Christ and His saving work. Through faith in Christ, Christians receive assurance that God forgives all their sins—past, present, and future—and have the sure hope of eternal life.
Through faith, Christians are justified (Rom. 5:1–2; Gal. 2:15–16). This means that in Christ, God declares a believer righteous rather than guilty (Rom. 8:1). This judgment is final. It cannot be reversed (Rom. 8:33–34). Christ earned the justification of His people by satisfying God’s justice in their place. In His life, Christ obeyed God’s law perfectly. When He died on the cross, He bore the curse of the law, paying the price for sin. Because of Christ’s work, Christians can be assured that God will not condemn them on the day of judgment. Instead, He will give them the kingdom He has prepared for them (Matt. 25:34).
Faith assures Christians that God does everything to save them. Through the Holy Spirit, He gives them new life (John 1:12–13). He adopts them as His children (Rom. 8:14–15; Eph. 1:5). He sanctifies them, forming in them the character of Christ (Phil. 1:6; Eph. 2:10; 1 John 3:2). He preserves their faith throughout all the dangers and temptations of this life (Rom. 8:35–39). He will glorify them with Christ in eternity (Rom. 8:30).
The promises of God in the gospel are magnificent (2 Peter 1:4). Yet Christians sometimes lack assurance of their salvation. One reason that Christians lack assurance is that often, in practice, they lapse into thinking that trusting in Christ alone is insufficient for salvation. They look for things in their lives that make them worthy of God’s favor. They look for signs that they are good enough to meet God’s perfect standard or have strong enough faith. But Abraham’s trust was not in his own performance. Nor does Christian assurance rest on the strength of one’s own faith. Faith does not earn God’s favor; it simply unites believers to Christ and all the blessings of the gospel. Assurance of eternal life can have no other foundation. Abraham didn’t trust in his own faith; he trusted God. We find assurance through faith not because of faith in itself but because of the One to whom faith unites us—the Lord Jesus Christ. We look to Him for assurance.
The book of Hebrews was written to a church that was tempted to return to the Old Testament law as a seeming means of salvation. The writer told that church, “Let us draw near with a true heart in full assurance of faith” (Heb. 10:22). He told them that Christians could approach God with “full assurance of faith” because when Christ died, He made the final sacrifice for their sin: “We have confidence to enter the holy places by the blood of Jesus” (Heb. 10:19). Christ, not their own works, made them fit to come to God.
The recipients of the book of Hebrews had professed faith in the gospel, and they needed to hear it again. This is true for all Christians. Assurance grows as believers keep hearing the gospel. This happens mainly through the ordinary means of grace. When Christians gather on the Lord’s Day to hear God’s Word preached and receive the sacraments by faith, their assurance is strengthened. Week by week, year by year, these means of grace grow a Christian’s faith in God’s promises.
Christian assurance can also be strengthened—or weakened—by the way that Christians live (2 Peter 1:10). Christ’s work is the foundation of assurance, but a growing love for God and other people can confirm that one has trusted in Christ. This change of character, called sanctification, is the result of justifying faith. It is a lifelong process, and it can have ups and downs. But all Christians experience an inner war between their sinful nature and their new nature in Christ (Gal. 5:17). As Christians daily turn from sin through repentance and trust in Christ, assurance usually grows. If they neither repent nor fight against sin, their assurance of salvation will weaken. At times, such contentment in sin reveals that a person has never actually trusted in Christ. But true Christians can go through such periods, and Christ will not let them go. Assurance often returns when they repent and renew their faith in the gospel.
Assurance of salvation also comes from the Holy Spirit, who lives in every Christian (Rom. 8:9). The Holy Spirit testifies to believers’ hearts that they are God’s children (Rom. 8:16–17). In fact, Christians are “sealed with the promised Holy Spirit, who is the guarantee of our inheritance until we acquire possession of it” (Eph. 1:13). The presence of the Holy Spirit testifies to Christians that they have peace with God and will receive the eternal life He has promised.
God wants Christians to have assurance of their salvation. He wants them to know that they belong to Him and are eternally safe in His hands. This assurance often grows over time, and it can be shaken even in mature believers. Temptations, sins, and overwhelming trials can lead believers to think that God has abandoned them (Ps. 88). But God never casts off those who have come to Christ. In times of darkness and doubt, Christians seek renewed assurance by fixing their minds on Christ, who is both the “founder and perfecter” of their faith (Heb. 12:2). God’s Word assures Christians that Christ, through His Spirit, preserves His people to the end.
Real assurance rests on a sound understanding of salvation, a sound understanding of justification, a sound understanding of sanctification, and a sound understanding of ourselves. In all these matters we have the comfort and assistance of the Holy Spirit who illumines the text of Scripture for us, who works in us to yield the fruit of sanctification, and who bears witness with our spirit that we are the children of God.
R.C. Sproul
“Fear Not”
Ligonier.org
Only Christ can save us, and assurance, when lacking, must be found by looking to Him. Apart from faith in Christ, no work on our part will assure us of anything except Pharisaism.
Derek Thomas
Tabletalk magazine