@stationary_seniorita - A very good question. The Bible mentions both of these points very clearly…though, the answer to your question may not be so easily accepted as it is easily given. I hope you’ll consider it all the same.

First, you asked, “What if someone has never committed a sin in their life…?”

I’ll try to keep this simple and short, but I think it’s worth saying that this question actually hits to a much deeper topic: that of a universal moral standard. Here’s what I mean… You question asks about someone who has supposedly never sinned…well, according to which

idea

 of what the moral standard is? Allow me to explain with an example…

Say you have a ball. The ball has a particular color. It is that color whether someone is around to see it or not. It is, essentially, an independent object whose state is not influenced by anything else.

Then come two people. Those people both see the same ball, however, at least one of them state that the ball is a color other than what it really is. The question is if what either of those say about the ball’s color actually defines the ball’s color or simply confirms it. If the ball’s color is green, then that ball will remain green even if I said it was blue. If I said it is green, then all I have done is to confirm what it already is. I did not define the ball’s color, for it was already green before I came about. Make sense? (If not, I’ll try to better illustrate.)

It’s very clear that everyone has an idea of what morals ought to be, let alone if there is or is not a universal moral standard. It’s certainly a difficult subject whether or not you believe in God or the Bible. However, if we’re to at least consider what the Bible has to say on the subject, then there is not one person who has lived since Adam who has not sinned (Jesus being the only exception). You might ask, then, what constitutes as a sin…another good question if you were to ask. Basically, a sin is anything that runs contrary to God’s commandments and standards for living. This requires much more in-depth discussion, so I’ll leave it at that for the moment.

In the book of Romans (see the New Testament half of the Bible), the Apostle Paul wrote to the Christians in Rome, “…all have sinned and fall short of the glory of God” (Romans 3:23). The “glory of God” entails a great many things, but is essentially the context here is that of God’s character. The Bible says that God is good. By His very nature, nothing about Him is evil or bad (I can better clarify on how that is if you like – just ask). God is the moral standard and He always acts according to His nature. The fault we humans make is to judge God according to our own ideas of what moral goodness is or is not. We assume that we have the higher moral ground…it’s not all unlike the entire mess that Satan tricked Adam and Eve with in the Garden of Eden, making them believe they, too, could be gods, and therefore not subject to God’s authority. We have assumed we have equal or greater authority to God.

Paul adds, “Now we know that whatever the law says it speaks to those who are under the law, so that every mouth may be stopped, and the whole world may be held accountable to God. For by works of the law no human being will be justified in his sight, since through the law comes knowledge of sin” (Romans 3:19-20). The Law of God was put in place to show how people were sinning against God. The Bible mentions that for a time God did not hold the people accountable for their sins – evidence of God’s patience and grace already. But when the Law was given, it was for the purposes of guiding the people back into a right relationship with God. It was like the guardrails on a road with a sheer cliff to the side. The Law could not save the people since the people were already so inclined to jump off the edge anyway. It was simply there to say, “Hey! Don’t go off the edge if you don’t want to die!” The Grace of God is where God saved people from their doom long after they had already jumped…
So, since no one is innocent, all are guilty (obviously, heh). And that’s a very serious matter…but there is hope. Not just wishful thinking, but an assurance.

But wait, as you asked, what if someone has never heard of Jesus? Paul also addressed that matter to the Roman Christians in the same letter (much of the New Testament books were letters written to the churches Paul helped to establish during his journeys of sharing the message and hope of Jesus).
So what of those who have not heard of Jesus or His Gospel (the good news)? Paul says this:

“He will render to each one according to his works: to those who by patience in well-doing seek for glory and honor and immortality, he will give eternal life; but for those who are self-seeking and do not obey the truth, but obey unrighteousness, there will be wrath and fury. There will be tribulation and distress for every human being who does evil, the Jew first and also the Greek, but glory and honor and peace for everyone who does good, the Jew first and also the Greek. For God shows no partiality.

For all who have sinned without the law will also perish without the law, and all who have sinned under the law will be judged by the law. For it is not the hearers of the law who are righteous before God, but the doers of the law who will be justified. For when Gentiles, who do not have the law, by nature do what the law requires, they are a law to themselves, even though they do not have the law. They show that the work of the law is written on their hearts, while their conscience also bears witness, and their conflicting thoughts accuse or even excuse them on that day when, according to my gospel, God judges the secrets of men by Christ Jesus” (Romans 2:6-16).

The parts I highlighted in the above two paragraphs will hopefully sum things up for you. Basically, if we accept that we are created in God’s image, and that image, by its own nature, is what is good, then anything lacking or apart from that image is evil (evil is simply what we call the LACK of good; not, as some wrongly conclude, its own separate entity). We were created in God’s good image, so , even though we are like broken figures modeled after our crafter, we still bear His likeness. That likeness is what proves that we are not innocent, for we can either respond instinctually to the moral promptings our likeness to God calls out to, or we can ignore them. We might not recognize that our moral promptings are actually a testimony to the fact that God created us in His image, but we still have that “built-in” moral standard which we can choose to ignore or not.

What does this mean? Ultimately, it means that even if one has not heard of Jesus or His message, the moral standard found in God is written into our nature, too. But we have the option to ignore that standard and do our own thing. Since all have ignored this moral prompting, with or without having heard of Jesus, all are guilty.

But don’t fret. As Paul explained, those who seek to obey those moral promptings – even though they may not realize that such promptings are connected to God – will actually find God’s grace. But those who revel in doing their own thing will not find such a happy ending.

I know that was a lot, and I tried to keep things to the point, but if I need to clarify anything, I’ll do my best to help you understand. I really do appreciate you stopping by. You’re quite welcome here.

@stationary_seniorita - Sounds like you got the idea.
I am confused, though, by what you mean when you asked if I could offer the explanation “without reading the Bible”.
Do you mean without having referenced Scripture?

@stationary_seniorita - Ultimately, no. Because the concept of Hell is predominantly a Biblical one. And Jesus is the crux of the entire message of Scripture. And when we discuss morality in terms of both Jesus and Hell, it’s virtually impossible to explain what I did without so much as referencing God’s Word. (Granted, I know I was lengthy, but that’s just my wordiness getting the better of me.)

Like I mentioned, that moral instinct isn’t just a random notion we humans have. It’s like a “hot/cold” sensor…like how close or far away from something you are. If our moral instinct is such a “sensor”, then the question has to be asked, “What are we sensing?” That “what” is God, Himself, the moral standard incarnate.