And then there are some who become apostates (like Judas) and fall away completely. John tells us these people went out from us because they were not of us. If they had been of us they would have continued with us. (
1 John 2:19)
What John wrote in 1 John 2 was in reference to a specific group of people. There’s nothing in that passage that indicates that it applies to everyone who apostatizes. That idea was formulated by reformed theologians to support the doctrine of eternal security. Heres the problem with the use of that verse. In John 15:2 Jesus says
“Every branch
in Me that does not bear fruit, He takes away; and every branch that bears fruit, He prunes it so that it may bear more fruit.”
John 15:2 NASB1995
The Greek word Aion that is translated to “takes away” in the NASB means to remove from its place and when used in reference to anything that is attached to something it means to cut off or remove. False professors are never joined to Christ. So when Jesus says every branch IN ME that means that they were in fact true believers.
2 Timothy 2:12 is another example. Paul wrote to Timothy and said this to him.
“If we endure, we will also reign with Him; If we deny Him, He also will deny us;”
2 Timothy 2:12 NASB1995
Here Paul tells Timothy that if he or Timothy were to deny Christ that He would deny them. Now if Paul or Timothy were to deny Christ that wouldn’t mean that they were never joined to Christ or that they were never true believers because we know for a fact that they were.
James 5:19-20 is another example.
“My brethren, if any among you strays from the truth and one
turns him back, let him know that he who turns a sinner from the error of his way
will save his soul from death and will cover a multitude of sins.”
James 5:19-20 NASB1995
Here James makes it clear that if one of the brethren strays from the truth his soul is in danger of death. But if another brother TURNS HIM BACK, which means turns him back to what he previously believed, then that brother will have saved his soul from death. This is telling us that just because someone turns away it doesn’t mean that they were never a true believer. If they were never a true believer then turning them BACK wouldn’t save their soul from death.
These are three examples that true believers can fall away and just because someone does fall away doesn’t mean that they were never a true believer.
Furthermore it also means that these people were drawn to Christ by The Father and they are still capable of falling away.
Here’s a few more verses verses that reformers misinterpret that contradict the scriptures above. John 10:28-29
“and I give eternal life to them, and they will never perish; and no one will 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 the Father’s hand.”
John 10:28-29 NASB1995
If I am holding a frog in my hand and I say no one can snatch this from from my hand that means that a third party cannot take the frog from my hand. It doesn’t mean that I said that the frog can’t jump from my hand and it doesn’t mean that I said that I can’t throw the frog from my hand.
Another one John 6:37
“All that the Father gives Me will come to Me, and the one who comes to Me I will certainly not cast out.”
John 6:37 NASB1995
The Greek word translated to “comes or cometh” is used only in the present and imperfect tense which means that only those who are presently or continuously coming to Him, He will not cast out. It doesn’t mean that anyone who ever came to Him he will not cast out. This particular Greek word is never used in the past tense.
Another one John 6:39
“This is the will of Him who sent Me, that of all that He has given Me I lose nothing, but raise it up on the last day.”
John 6:39 NASB1995
Here Jesus is not saying that He will lose none. I’ve seen so many people misquote this verse by leaving out the first 9 words “it is the
will of Him who sent Me”. The Greek word translated to “will” in this verse does not always mean something that God has decreed. It can also mean something that God desires. The same Greek word is used in 1 Timothy 2:4 the only difference is John 6:39 uses the noun form and 1 Timothy 2:4 uses the verb form but they both have the exact same definition.
So your application of 1 John 2:19 is incorrect.