This study by Columbus, OH Pastor David Reid came up on my YouTube feed: "Can Those Who Rejected the Gospel Before the Rapture Still Be Saved After the Rapture?"
Reid answered:
Can you get to the Great White Throne Judgment and say, "Look, I'm a fence-sitter. I heard the gospel but hadn't come to a conclusion and now I have; I believe it." Are you going to have that opportunity? You're not, because when you hear the gospel and you don't accept it, you know what you did? You rejected it, right?
The gospel is a command. The Philippian jailer asks in Acts 16:30, "Sirs, what must I do to be saved?" and the answer was, "Believe on the Lord Jesus Christ, and thou shalt be saved, and thy house."
Paul does not say, "Well, my suggestion, it's just one possibility of many, but consider believing on the Lord Jesus Christ and then you'll be saved." He doesn't say that. He specifically says, "Believe on the Lord Jesus Christ and thou shalt be saved."
That belief is an imperative; it's a command. If I say, "Shut the door!" what is the subject of that sentence? You, because it's a command. "Close the window!" "Stop the nonsense!"
Every single one of those is an understood "you," because it's an instruction to do something. So to the question, "What must I do to be saved?" Paul is not making a kind suggestion. He's issuing a loving command that, "You need to believe on the Lord Jesus Christ, and if you don't you'll be accountable for your own sins."
The duty of all men is to believe the gospel and the failure to believe the gospel is the decision, "My own righteousness is sufficient, and I'll handle the sin problem myself," and when you decide that you will, but it won't turn out well.
So, now, let me ask you this. How many people on earth haven't heard enough of the gospel to be accountable? Is there anyone on earth who doesn't have enough information so that they aren't accountable before God?
Now, I'm going to make an exception here. It's different for children and it's different for those who lack the mental capacity to understand.
But let's talk about normal adults. Has the grace of God appeared to some men, or has it appeared to all men? Are there those out there who haven't heard or did Paul answer that question, "Yes, verily their sound went into all the earth"? Scripture says that all men are without excuse.
Romans 10: [18] But I say, Have they not heard? Yes verily, their sound went into all the earth, and their words unto the ends of the world.
Can those who reject the gospel prior to the Rapture be saved afterward? The answer is "Yes, they can because there's no men who are without excuse."
But let me say this, it makes no difference in the following sense. First of all, there's a possibility that I'm wrong and those who rejected the gospel before the Rapture maybe can't get saved afterward. I wouldn't bet your eternal destiny on whether or not I'm right on this.
Secondly, so do you wait after the Rapture to get saved? Do you look at things and say, "Well, I'm not sure about this. Let's just wait. If the Rapture happens, I'll know it's true and then I'll get saved."
Is that wise? That is just beyond dumb. If you do that, the first thing that's going to happen is now you've got to live through the 70th Week and you could have avoided it! So that doesn't make any sense.
But even more fundamentally, if you say, "Well, I'm going to wait and decide later," raise your hand and tell me the day you're going to die. You don't know, so you may not make it to the Rapture. In fact, everyone in time past who has thought that has so far been wrong.
II Corinthians 6: [2] (For he saith, I have heard thee in a time accepted, and in the day of salvation have I succoured thee: behold, now is the accepted time; behold, now is the day of salvation.)
So, according to Scripture, when is the proper time to get saved? Now, immediately, if not sooner! You don't know if you're going to live another day.
I was once on a doorstep talking to a young lady and she said, "I hear you but I'm going to get saved later in life," and she was saying essentially that she had some things she wanted to do. Is that wise? I mean, that's just very, very foolish because you don't know how long you have.