There is a teaching among many Protestants that goes by a few different names: eternal security, perseverance of the saints, once saved always saved. Three different names for the same exact doctrine: once you are “saved,” once you have faith that both (1) produces repentance (because forgiveness of sins is part of grace, and there is no forgiveness without repentance) and (2) allows you to receive the grace of God (grace is a gift from God for your faith), you can never lose that salvation. You will go to Heaven. No matter what. As John Calvin himself put it, “once saved, a person is always saved.”
Which is why I think the last of those names, once saved always saved, sometimes abbreviated OSAS, is the best name for the teaching. The other two aren’t wrong to describe it, strictly speaking, but can be misleading. They say nothing of the mechanism of how this doctrine, in and of itself, actually works. Furthermore, to say you’re against those names (perseverance of the saints or eternal security) seems counter intuitive to most Christians. Those who are going to Heaven will persevere. If you are of faith, you are being kept at this very moment by God (1 Peter 1:5), Who is eternal. Your security is eternal. Those who are going to Heaven will persevere. No Christian denies these things, but many Christians are uninitiated in the set of things to which those labels actually refer.
OSAS is a more accurate depiction of the doctrine, because it more accurately depicts the sequential logic as taught by that doctrine: you will persevere because you are a saint. I intend to show how this teaching is contrary to the Biblical, Orthodox view: you are a saint (which is to say you are in Christ’s Church, whether in this earthly plane of existence or not) because you persevere.
The Bible says you are kept by God if and only if you are of faith. 1 Peter 1:3-7:
3Blessed be the God and Father of our Lord Jesus Christ, which according to his abundant mercy hath begotten us again unto a lively hope by the resurrection of Jesus Christ from the dead, 4To an inheritance incorruptible, and undefiled, and that fadeth not away, reserved in heaven for you, 5Who are kept by the power of God through faith unto salvation ready to be revealed in the last time. 6Wherein ye greatly rejoice, though now for a season, if need be, ye are in heaviness through manifold temptations: 7That the trial of your faith, being much more precious than of gold that perisheth, though it be tried with fire, might be found unto praise and honour and glory at the appearing of Jesus Christ:
It is through your faith that you are kept by the power of God. To lose that faith is to lose that Heavenly reservation. This is a point Peter wanted to make very clear, because the faith of the letter’s recipients was to be “tried with fire.” Only if their faith persevered were they to be “found unto praise and honour and glory at the appearing of Jesus Christ.” That’s why the statement is qualified with “might”
The Bible says your name will be blotted out of the Book of Life if you sin against God. Revelation 3:4-5, Exodus 32:33:
4Thou hast a few names even in Sardis which have not defiled their garments; and they shall walk with me in white: for they are worthy. 5He that overcometh, the same shall be clothed in white raiment; and I will not blot out his name out of the book of life, but I will confess his name before my Father, and before his angels.
33And the LORD said unto Moses, Whosoever hath sinned against me, him will I blot out of my book.
Sin separates you from God. Being “saved,” doesn’t prevent this, because you are not in the Book of Life unless you are saved (Daniel 12:1, Revelation 21:27).
The Bible says your salvation can be lost. Galatians 5:3-5:
3For I testify again to every man that is circumcised, that he is a debtor to do the whole law. 4Christ is become of no effect unto you, whosoever of you are justified by the law; ye are fallen from grace. 5For we through the Spirit wait for the hope of righteousness by faith.
If you take your faith from the Spirit and put it in the law, Christ is “become” of no effect unto you. He can’t “become” of no effect unless He once was of effect. At that point, you are “fallen from grace.” Grace is a thing you had, but it’s gone. This is completely contrary to OSAS.
The Bible calls upon you to “make your calling and election sure.” 2 Peter 1:4-10:
4Whereby are given unto us exceeding great and precious promises: that by these ye might be partakers of the divine nature, having escaped the corruption that is in the world through lust. 5And beside this, giving all diligence, add to your faith virtue; and to virtue knowledge; 6And to knowledge temperance; and to temperance patience; and to patience godliness; 7And to godliness brotherly kindness; and to brotherly kindness charity. 8For if these things be in you, and abound, they make you that ye shall neither be barren nor unfruitful in the knowledge of our Lord Jesus Christ. 9But he that lacketh these things is blind, and cannot see afar off, and hath forgotten that he was purged from his old sins. 10Wherefore the rather, brethren, give diligence to make your calling and election sure: for if ye do these things, ye shall never fall:
The Holy Spirit though Peter tells Christians that if they “do these things” then “ye shall never fall.” Not “ye shall never fall,” therefore “do these things.” Again, it’s not that this is an atrocious doctrine, it’s that the sequential logic of OSAS is completely backwards, and that has heretical logical implications (as seen above).
Aside from that, verse 9 says someone can forget he was purged from his old sins. Someone can be purged from his old sins (saved) and then not do these things, and then possibly fall. It is only by doing “these things” that “ye shall never fall.”
The early Church Fathers clearly believed someone could be saved and then lose their salvation. From Polycarp’s letter to the Philippians:
I was exceedingly grieved for Valens, who aforetime was a presbyter among you, because he is so ignorant of the office which was given unto him. I warn you therefore that ye refrain from covetousness, and that ye be pure and truthful. Refrain from all evil.
I don’t wish to elevate the writings of Polycarp to the level of scripture. It’s not scripture. What it does demonstrate, though, is that at least one (the most significant of the 2nd century, Polycarp was a disciple of the Apostle John) early church father clearly believed someone had been saved and lost their salvation. Valens was an elder, which means he had to be saved (Titus 1:8). Then he fell away.
What’s true? Persevere. God commands it. Obey 2nd Peter 1, and you won’t fall. Keep the faith, and you will be kept by God. Commanded Perseverance is the doctrine of Christianity. Once Saved Always Saved is a man made heresy.