One of the things that makes it hard to explain things about Judaism to non-Jews is that most non-Jews I interact with grew up in a world dominated by Christian ideas of what religion is. And the thing is, Christianity redefined the idea of what "religion" meant. Pre-Christian religions and post-Christian religions generally look pretty different.
Generally speaking, people whose primary exposure to religion is through Christianity or Islam assume that religion is about what you BELIEVE. But in most religions other than those two and their daughter religions, belief is kind of a secondary thing. It's not NOT there, but it's one of many pieces, and not one of the most important ones. This is why there's no fundamental conflict between being an atheist and a Jew -- or, perhaps more accurately, to the extent that there IS a conflict, it is one that is well-established and respected in modern Jewish culture and history.
Lack of belief in Jewish theology isn't a major problem in Judaism.
However, the reason you can't be Christian or Muslim, and Jewish is because THOSE religions ARE belief-based. Lacking belief in Judaism isn't an insurmountable problem to being Jewish. But HOLDING belief in something that ISN'T Judaism IS a big honking insurmountable problem. It's one of the only ways you CAN give up your Judaism.
As one of my friends has said, "I don't believe in God. And the God I don't believe in is the God of Abraham, of Isaac, and of Jacob."
People ask if Judaism is a religion, a race, or both. And most Jews will answer that with "both", but I think the better answer is "it's not that simple."
Judaism dates from a time before religion, family, tradition, culture, language, and land were different things. We're not just a mixture of those things -- we are a thing that encompasses all of those things. As the millenia have gone on, and as those became discrete concepts in human cultures, we've sort of shifted and switched around and modified to try to fit into those new models, but, at our core, we're just plain older than that. One phrase we use, light-heartedly and kind of joking-not-joking, is "MOT" -- "member of the tribe." And thinking of us a a tribe gets a little closer than "race" or "culture" or "religion".
The fact that we're ... whatever the heck we are ... means that our religion doesn't really work on the same expectations as Christian and post-Christian religions. We're just about different things.
Here's a question that is interesting from a Jewish perspective:
So, you've got two bowls of water. Water flows into the top bowl, then spills over and flows into the bottom bowl. And the bowls and the water are both in a state of taharah. Now, if the TOP bowl becomes tamei, obviously the water that flows from the bowl into the other bowl is tamei, and the second bowl becomes tamei.
But what if the BOTTOM bowl becomes tamei? Does the TOP bowl become tamei?
Note that, to even understand the question, you have to understand what "tamei" and "tahor" mean, and that's really not an easy question to explain in the first place. People translate it as "ritually impure" and "ritually pure", but that's just an approximation of the term; they don't REALLY fit as translations, and I have no real idea how to explain them, even if I fully understood them, which I don't.
So, yeah, this one is a question you can really sink your teeth into, and it's the kind of question that MATTERS.
Here's a question that is boring from a Jewish perspective:
What happens to us after we die?
Oh, as individual people, sure, we are interested in that sort of thing, and Jews have come up with answers to that all throughout history. Which is why Judaism believes in Heaven, bodily resurrection, reabsorbtion into God with the loss of self and individual consciousness, reincarnation, and GAME OVER. As well as others. Basically, Jews have a tendency to pick up modifications of the afterlife beliefs of the other cultures we live among. Because Judaism, as Judaism, fundamentally isn't interested in the question.
So one of the difficulties in explaining Jewish topics to people who didn't grow up in a Jewish context is that the questions that people are asking are often category errors. It's like asking "how many grams of protein are in that memory of the smell of a rosebush that summer?" or "how long does it take to drive to purple?"
Yes, we also have practical questions that people can understand, like, "Say you were bulding a wall, and some construction materials fell into the street, and someone tripped on them and injured themselves -- how much do you pay in damages?" "If you have someone guarding your property and you get robbed anyway, under what circumstances is the guard responsible for making up your loss?"
And practical questions that might NOT make sense to outsiders, like "Does the Law say that you start counting the Omer from the morning after the Sabbath OF Passover (i.e., the beginning of the holiday of Passover is a Sabbath), or the morning after the Sabbath IN Passover (Passover is a week long holiday -- a day longer outside Israel to make sure that you cover the whole thing -- so it will always include a Saturday)?" That one nearly led to a civil war... (It makes sense in context. Basically, the entire cycle of sacrifices in the Temple is tied to the Omer count, so pretty much the entire religious chunk of the year would be different depending where you start.)
We have a history, a culture, a religion, a family, a belief system, a law code, a nation, a tribe, a people. We ARE a history, a culture, a religion, a family, a belief system, a law code, a nation, a tribe, a people. And since most people in the modern world don't usually deal with this particular amalgamation of ideas as a single thing, it's hard to get across.
Posted at https://xiphias.dreamwidth.org/803810.html; you can comment there or here. There are comments over there.