The issue of eternal security is one in which professing Christians hold a wide variety of viewpoints. Some say that salvation is something we can get and then give away by wrong behavior and then get yet again if we turn back to Christ. Another viewpoint suggests that we cannot ever know for sure if we are saved or not because this is a mystery of the Scripture that cannot be solved. Others believe that once saved, always saved. Which viewpoint is correct? Can we answer this question from the Scripture or is Scripture silent on the issue? Does it even matter? May I make the assertion that all of Scripture is inspired by God and profitable for teaching, reproof, correction, and training in righteousness to make the believer fully equipped and ready and able to do the good works we are called to do (2 Timothy 3:16-17). Since Scripture says of itself that we are not to discount portions of it as if certain issues are peripheral or nonessential, we must be willing to explore and investigate prayerfully and by faith even the passages that create division and controversy in the church. A whole new generation of professing believers is rising up that doesn’t think it is worth their time to dig into doctrine. They are satisfied simply to "love one another" and "love God." Certainly those are good things since God is love, but Jesus is also the truth. The truth sets us free, Jesus said, and He also said that His Word is truth (John 17:17) and that He Himself was the truth (John 14:6). So truth matters to the utmost extent according to Jesus, and He would be disappointed with us if we were to neglect the truth He has given us in His Word. As the body of Christ, we cannot brush aside the issues for the sake of "community" and "harmony" in the body. Rather, we must humbly and with grace toward one another patiently and steadfastly search the Scriptures. I grant that there will be disagreement, some of it quite passionate, when issues such as eternal security are brought up. Well, may I suggest to you that apathetically "agreeing to disagree" is a far worse decision than humbly and graciously seeking out the truth together? Doctrine both divides and unifies; therefore, right doctrine is the only means to bringing true unity (Ephesians 4:11-16). When we start compromising on the importance of the whole counsel of God, our teaching will become mere "ear-tickling," and the entire church will suffer and grow weak and vulnerable to the deceptions of the world (2 Timothy 4:3). So here is the truth that I believe we must seek and believe.
Eternal security is a theological term for a concept derived from the Scripture. The term has its shortcomings in that it seems to imply that once we are saved, it doesn’t matter how we live because we have a "get out of hell free card" in our back pocket. The terminology itself seems to open the door to sinning such that grace may abound, which Scripture emphatically prohibits (Romans 6:1). God cares how we live in this life, and those who are truly saved, though they may rebel at times, are those who have been made new in Christ (2 Corinthians 5:17) and who are led by Him (Romans 8:14). A professing Christian who has little if any desire for obedience or for the glory of God definitely needs to be introspective as to the true state of his heart. There is a reason that Scripture says that we will be known by our fruit or the lack thereof (Matthew 7:20).
Some argue that if we are safe in Christ that there is no incentive to be holy. These miss the idea that Christ changes hearts to be compelled, even controlled, by love (2 Corinthians 5:14). The Spirit of God makes us want to be holy, and we experience sorrow when we sin (Psalm 51). The true Christian does not delight in evil, but the kindness of God keeps moving him to repent as he sees how God’s ways are the best ways and more desirable (Romans 2:4). It is also important to remember that how we live in this life impacts how we will be rewarded in eternity (2 Corinthians 5:10, 1 Corinthians 3:10-15). Thus, there is both an internal and external motivator for holiness.
I believe the Scripture when it speaks of the Holy Spirit being a guarantor of our salvation (Ephesians 1:13). I believe the Scripture when it speaks of Christ being the author and finisher of our faith (Hebrews 12:2). I believe God when He says that Christ will finish the good work He started in our hearts (Philippians 1:6). I believe that nothing can snatch us out of the hand of Christ (John 10:28). I believe that God is able to keep His own (Jude 24), and I believe that nothing can separate us from the love of God (Romans 8:38-39). Romans 8:30 says that those who have been saved will also be glorified. God doesn’t see salvation as an uncertain process, but He sees the finished product from the beginning from before we are even conceived. He knows our end, and thus it is true that He calls us and will keep us. This is true not because we are deserving or powerful in and of ourselves, but it is because we are safe in His arms because His love is sure.
As adopted children of God and joint inheritors of heaven with Christ (Romans 8:14-17), our God will never destroy our adoption papers or remove our inheritance. We are safe not because we will never stumble, but we are safe because He never fails (2 Timothy 2:13). If such love doesn’t motivate us to holiness, nothing will.