Why would an atheist come to Christ, if not to avoid hell?

There isn't a demonstration available to show you God, sorry. But if you look into some of the other understandings of God that philosophers like Plato produced you will realize there is a reason for that. After you get up to speed on a rational understanding of God then we could discuss its limits.

So how do you plan on discussing this rational God then? How do we verify that such a God is indeed rational?

I have studied several "understandings of God" I have not found any of them to be particularly rational.

To help me understand the limits of God, what is bigger than God?

I didn't plan on discussing it. I assumed you were familiar with it enough to change your response from "explain" to "demonstrate", which meant you were aware enough to ask for empirical evidence for spiritual elements, as the standard routine for denial of anything but matter. What is the possibility that you are unaware of the contributions of Socrates and Plato on Western thinking? I'm sure you are aware of what I consider a rational understanding but since it can't be proven with a material demonstration it's easy for you to disregard as irrational.

No, I'd have to see where you take it before I can comment on it. And since it apparently cannot be demonstrated or explained I would necessarily have to disregard it as irrational.

It can be explained but that's not the demand that is being made, you want physical proof for something that isn't physical, and when you don't get what can't be had you say that is your justification to doubt its existence.

SOCRATES: Take a look round, then, and see that none of the uninitiated are listening. Now by the uninitiated I mean the people who believe in nothing but what they can grasp in their hands, and who will not allow that action or generation or anything invisible can have real existence." Theaetetus

Nevertheless, it doesn't particularly matter who said it, do you think this quote explains something?
Let me give you another "Socrates" quote: "I only know that I know nothing."

I'll try.

Let's start with matter and work our way back I guess. Before Socrates, materialism was the dominate thinking coming from the natural philosophers.

Now if you understand the limits of your perception and consider the possibility that the spiritual side of the universe exists, (Not in the superstitious understanding of the spiritual realm you are familiar with but a rationally understood ordering principle at work to produce the phenomenon we see in the universe.)

To be fair, natural philosophers, suggests that materialism is a necessity.

So those things we can't perceive are unchanging?

So what you're getting at here is that these things may exist, or may not exist. That seems rational. However, if we say that they do exist just on faith, then we make that statemnt arbitrarily, and we cannot also say that it is rational.

Again, while considering the possibility that a spiritual side of the universe exists may be rational, claiming that a spiritual side does exist simply on faith, is arbitrary and irrational.

Okay, how do we know that things without bodies are indistinguishable from other things without bodies in the spiritual realm?

I wouldn't exactly label myself as someone who believes in the big bang, as I have rudimentary understanding of it, and cannot adequately judge whether I actually believe it or not.

That might be so, but a deist wouldn't necessarily say that God exists.

Not necessarily. We are working with a very loose concept of God. For instance I know several pantheists who would say that God does not exist, as simply labeling existence as God is redundant, and unnecessary. I would suggest that labeling God as first cause runs the same problem.

You have also separated God so far from it's classical, and common definition that the vast majority of actual theists would argue that your definition is not God. In fact, I'm having trouble finding a common definition of God that supports yours.

That might be so, however, I am not strictly a materialist. I am however agnostic, and have serious problems claiming knowledge and making intended factual statements about things I don't believe I understand.

As opposed to what?

Yeah, that’s the basic idea behind platonic duality.

“For the images which are presented to the sight in executed things are subject to dissolution; but those which are presented in the One uncreate may last for ever, being durable, eternal, and unchangeable” Philo Allegorical Interpretation

2 Cor 4:18 “As we look not to the things that are seen but to the things that are unseen. For the things that are seen are transient, but the things that are unseen are eternal.”

I agree that there is no certainty to be had but by definition “faith” is the belief in the unseen but if that belief is rational or not, depends on if reason is used to support that belief, in comparison to the reason to support the other option. For example not having any empirical evidence for spiritual elements is a common reason to believe in pure materialism but when considering physical evidence of non physical entities isn’t possible that becomes irrational reasoning for that belief.

They aren’t distinguished in that they are separated by time and space with bodies. They are distinguished by their effect, similar to as Paul points out “Now there are varieties of gifts, but the same Spirit;”

It’s not about understanding the current theories of how the universe started but having an opinion if the universe had a beginning at all, or has the universe been around for an infinite amount of time. On the surface a universe that has been around an infinite amount of time is impossible because it is an imaginary number that has no end.

I would say that a pantheist isn’t speaking about God but the universe, but if you are speaking of the creative principle of the universe then you are speaking of God.

Regardless if you think it is a guy with a white beard in the sky who hates pork or you think of it in more rational terms. You may be correct about the majority are working with a superstitious understanding of God but that isn’t the understanding that Christianity is founded on.

“That which always maintains the same nature, and in the same manner, and is the cause of all other things—that, indeed, is God.” Justin Martyr Dialogue with Typhro the Jew.

The constant understanding of the spiritual elements may not have been in the majority but those who could read, write and leave us texts weren’t going to take poetry literally, producing superstitious (classic) understandings of the gods. The accusation that if the understanding of God isn’t what was assumed by opponents then it isn’t God goes back to Socrates and the early Christians.

“Hence are we called atheists. And we confess that we are atheists, so far as gods of this sort are concerned, but not with respect to the most true God, the Father of righteousness and temperance and the other virtues, who is free from all impurity.” Justin First apology.

Certainly you don’t want to try to form an opinion until you have considered and researched the positions. What you don’t want to do is be familiar with the conversation and still demand physical proof for spiritual elements or act like you are incapable of forming an opinion so you are agnostic.

When I demand physical proof, I'm essentially saying "how do you know without evidence?" Why is the position that God is an unchanging spiritual force that cannot be detected, more rational than God is an old guy, with a long beard, who hates pork, living in the clouds, that cannot be detected? How are either one more rational than the claim that B.B. King is actually God?

I have long favoured the early Vedic tradition, which is not far removed from pantheism (but mixed with what would be Taoism), but that is only to say that I like it. The problem is that it begins with a set of presupositions that are simply taken on faith. It is not my opinion, I don't believe it, I certainly wouldn't make the claim that it is factual, rational, or correct. It is merely a position that interests me.