Eternal security is the work of God whereby the gift of salvation, once accepted, is eternally guaranteed. Lewis Sperry Chafer in his Systematic Theology defines eternal security as follows: "No individual once the recipient of the saving grace of God will ever fall totally and finally from that estate, but he shall be 'kept by the power of God through faith unto salvation,' 1Peter 1:5." The very offer of salvation contains the promise of eternal security. In addition, many passages of Scripture strongly and clearly set forth the principle of eternal security. No one and nothing can cause the believer to lose his salvation. Furthermore, eternal security does not depend on anyone's experiences or emotions, and it is effective regardless of whether an individual realizes it or not.
Essential to the correct understanding of eternal security is the principle that eternal security is solely a work of God. "Who are kept by the power of God . . ." First Peter 1:5. The popular phrase "the perseverance of the saints" often used to describe eternal security, is at best misleading, or worse, flat out wrong, because it suggests that "the saints" are somehow involved in their own security. Actually, if the believer was involved in maintaining his own security, then eternal life could not be the free gift Scripture clearly declares it to be, "But the gift of God is eternal life in Christ Jesus our Lord," Romans 6:23, "For by grace you have been saved through faith, and that not of yourselves; it is the gift of God," Ephesians 2:8, "If you knew the gift of God, and who it is who says to you, 'Give Me a drink,' you would have asked Him, and He would have given you living water," John 4:10. Furthermore, as a sinner, man's works have no merit in God's eyes, Romans 3:10. Only Christ's merit given to those who put their faith in Him makes them righteous before God. Therefore, it is impossible for one's "good" works to contribute to his salvation or security in any way. Correspondingly, since the believer's works did not bring about his security, any failure on his part has no bearing on his security. In other words, a person, once a believer, can do nothing to enhance or endanger his eternal security. So, God alone has the power to keep the believer eternally secure because He is "greater than all," John 10:29. Since the believer's security rests solely on God, there is nothing that can destroy that security.
In examining the meaning of eternal security, let us begin with Christ's offer of salvation to us. In John 3:16 Jesus Christ says, "For God so loved the world that He gave His only begotten Son, that whoever believes in Him should not perish but have everlasting life." Christ clearly promises "everlasting life" to those who believe in Him. "Everlasting life" could not be everlasting if it could be lost or in any way invalidated. Thus, in the very message of the gospel, Jesus Christ makes clear that the free gift He offers cannot be lost, ever. Eternal life is the possession of the believer in Christ forever!! Additional passages: John 3:36; 5:24; 6:40, 47.
"And I give them eternal life, and they shall never perish; neither shall anyone snatch them out of My hand. My Father, who has given them to Me, is greater than all; and no one is able to snatch them out of My Father's hand," John 10:28&29. "For I am convinced that neither death, nor life, nor angels, nor principalities, nor powers, nor things present, nor things to come, nor height, nor depth, nor any other created thing, shall be able to separate us from the love of God which is in Christ Jesus our Lord," Romans 8:38&39. These two passages of Scripture clearly teach that no one and nothing can destroy the believer's eternal security. In John 10:28&29 Jesus Christ Himself assures us that those who believe in Him will never perish. God closes His hand around the believer and no one can take him out of God's hand. In Romans 8:38&39 Paul declared the certain knowledge that nothing in all of creation can separate the believer from the love of Jesus Christ our Savior. Another passage supporting eternal security is found in Romans 8:30, "Moreover whom He predestined, these He also called; whom He called, these He also justified; and whom He justified, these He also glorified." Here Paul asserts that all those who God predestined and justified, He also glorified. If any one of those whom God predestined and justified could lose their salvation, then the number God predestined and justified would not be the same as those whom He glorifies. Furthermore, so certain is the glorification of those predestined and justified that the writer uses the past tense: glorified. It is as good as already done. Thus this verse reinforces the believer's eternal security. Additional passages: John 6:39&40; Hebrews 7:25; Jude 24.
Can you lose your salvation if you commit a really bad sin? When Jesus Christ paid for our sins on the cross, He satisfied God's righteousness and justice. In so doing, He permanently eliminated sin as an issue in salvation. The issue for those who reject Jesus Christ is not their sins; it is their rejection of Christ. Similarly, those who believe in Christ are seen by God in light of Christ's righteousness. Believers are not seen in light of the imperfect lives they lead (we are all sinners, Romans 3:10). Furthermore, all imperfections or sins are seen by God as the same: sin and evil and thus intolerable. But they have all been paid for by Jesus Christ. Therefore no sin, no matter how serious we may see it as being, can result in loss of salvation. God will continue to extend His grace to us, no matter what we do.
What if someone denies Jesus Christ and renounces his belief? Is he still saved? Salvation occurs at a moment in time. When someone believes in Christ he receives eternal life instantly and that gift is his forever after. Even if he openly renounces his belief, he will not lose his salvation. Let me give some Scriptural support. First of all, The Bible clearly teaches that no one and nothing can cause anyone to lose their salvation. No exceptions, no qualifications, John 10:28&29, Romans 8:38&39. Second, the Apostle Paul declared in 2 Timothy 2:13: "If we are faithless, He remains faithful; He cannot deny Himself." Jesus Christ always remains faithful to the one who believed in Him, even if the believer is not faithful. Finally, in John 13:38 Jesus Christ predicted that Peter would publicly deny Him. If denying Christ resulted in loss of salvation, Jesus should have told Peter something like "watch out; you are in danger of losing your salvation." But not so! Jesus went on to say, "Let not your heart be troubled; you believe in God, believe also in Me. In My Father's house are many mansions; if it were not so, I would have told you. I go to prepare a place for you," John 14:1&2. There is no loss of salvation here. Rather, there is encouragement and assurance of the disciples' eternal security, and that included Peter.
How do I know if I'm saved? First, let's start with the basics of salvation. Jesus Christ promises that those who have faith in Him will receive the free gift of eternal life, John 3:16. Faith is the only requirement for salvation; no work, no merit on our part, only faith. That is all God asks and all He will accept. Furthermore, salvation can occur any time, anywhere. There are no special requirements (e.g. posture, words, prayers, etc.), only simple faith. Second, salvation and eternal security are not based on any kinds of feelings, emotions or experiences. You may or may not know when you believed in Christ. Some people can pinpoint an exact moment when they know that they accepted Christ. Others just come to a realization over time that they have believed in the claims of Christ. Still others believe when they are too young to remember. All of these are equally saved and all have eternal security. Furthermore, one's assurance of eternal life/eternal security is based on belief in the infallible promises of Scripture, not on one's feelings and emotions.
Why is eternal security is so important? As believers in Jesus Christ, we have an adversary called Satan. It is his objective to render us useless to the Lord, and he will use anything in his power to accomplish this objective. If we could lose our salvation, all our hope, our confidence would be destroyed and we could not effectively serve the Lord. We would never know from one moment to the next whether we were really saved. Therefore, the promises of eternal security given in the Bible are critical to our ability to serve the Lord. Unfortunately, however, Satan still attacks the believer's assurance of eternal security. Those who understand the clear teachings of Scripture can easily deal with these attacks: God promised, and He will deliver. However, those who are deluded by false teachers or misunderstandings of Scripture are hindered in their service to God by doubts of their eternal security.
In conclusion, eternal security is the work of God whereby the gift of salvation, once accepted, is eternally guaranteed. By exercising faith in Jesus Christ, man acquires eternal life, a gift which is truly eternal. Furthermore, as believers in Christ, we trust in God's promises to us that we will never lose our salvation. No one and nothing can cause the believer to lose his salvation.