Question: "If our salvation is eternally secure, why does the Bible warn so strongly against apostasy?"
Answer: The Bible teaches that everyone who is born again by the power of the Holy Spirit is saved forever. We receive the gift of eternal life (John 10:28), not temporary life. Someone who is born again (John 3:3) cannot be “unborn.” After being adopted into God’s family (Romans 8:15), we will not be kicked out. When God starts a work, He finishes it (Philippians 1:6). So, the child of God—the believer in Jesus Christ—is eternally secure in his salvation.
However, the Bible also contains some strong warnings against apostasy. These warnings have led some to doubt the doctrine of eternal security. After all, if we cannot lose our salvation, why are we warned against falling away from the Lord? This is a good question. First, we must understand what is meant by “apostasy.”
An apostate is someone who abandons his religious faith. It is clear from the Bible that apostates are people who made professions of faith in Jesus Christ but never genuinely received Him as Savior. They were pretend believers. Those who turn away from Christ never really trusted Him to begin with, as 1 John 2:19 says, “They went out from us, but they did not really belong to us. For if they had belonged to us, they would have remained with us; but their going showed that none of them belonged to us.” Those who apostatize are simply demonstrating that they are not true believers, and they never were.
The Parable of the Wheat and the Tares (Matthew 13:24–30) provides a simple illustration of apostasy. In the same field were growing wheat and “false wheat” (tares or weeds). At first, the difference between the two types of plants was undetectable, but as time went on, the weeds were seen for what they were. In the same way, in any given church today, there may be true, born-again believers side by side with pretenders—those who enjoy the messages, the music, and the fellowship but have never repented of their sins and accepted Christ by faith. To any human observer, the true believer and the pretender look identical. Only God can see the heart. Matthew 13:1–9 (the Parable of the Sower) is another illustration of apostasy in action.
The Bible’s warnings against apostasy exist because there are two types of religious people: believers and unbelievers. In any church there are those who truly know Christ and those who are going through the motions. Wearing the label “Christian” does not guarantee a change of heart. It is possible to hear the Word, and even agree with its truth, without taking it to heart. It is possible to attend church, serve in a ministry, and call yourself a Christian—and still be unsaved (Matthew 7:21–23). As the prophet said, “These people come near to me with their mouth and honor me with their lips, but their hearts are far from me” (Isaiah 29:13; cf. Mark 7:6).
God warns the pretender who sits in the pew and hears the gospel Sunday after Sunday that he is playing with fire. Eventually, a pretender will apostatize—he will “fall away” from the faith he once professed—if he does not repent. Like the tares among the wheat, his true nature will be manifest.
The passages warning against apostasy serve two primary purposes. First, they exhort everyone to be sure of their salvation. One’s eternal destiny is not a trifling matter. Paul tells us in 2 Corinthians 13:5 to examine ourselves to see whether we are “in the faith.”
One test of true faith is love for others (1 John 4:7–8). Another is good works. Anyone can claim to be a Christian, but those who are truly saved will bear “fruit.” A true Christian will show, through words, actions, and doctrine, that he follows the Lord. Christians bear fruit in varying degrees based on their level of obedience and their spiritual gifts, but all Christians bear fruit as the Spirit produces it in them (Galatians 5:22–23). Just as true followers of Jesus Christ will be able to see evidence of their salvation (see 1 John 4:13), apostates will eventually be made known by their fruit (Matthew 7:16–20) or lack thereof (John 15:2).
The second purpose for the Bible’s warnings against apostasy is to equip the church to identify apostates. They can be known by their rejection of Christ, acceptance of heresy, and carnal nature (2 Peter 2:1–3).
The biblical warnings against apostasy, therefore, are warnings to those who are under the umbrella of “faith” without ever having truly exercised faith. Scriptures such as Hebrews 6:4–6 and Hebrews 10:26–29 are warnings to “pretend” believers that they need to examine themselves before it’s too late. Matthew 7:22–23 indicates that “pretend believers” whom the Lord rejects on Judgment Day are rejected not because they “lost faith” but because the Lord never knew them. They never had a relationship with Him.
There are many people who love religion for religion’s sake and are willing to identify themselves with Jesus and the church. Who wouldn’t want eternal life and blessing? However, Jesus warns us to “count the cost” of discipleship (Luke 9:23–26; 14:25–33). True believers have counted the cost and made the commitment; apostates fail to do so. Apostates had a profession of faith at one time but not the possession of faith. Their mouths spoke something other than what their hearts believed. Apostasy is not loss of salvation but evidence of past pretension.