Here's a comment written by E The P which deserves a wider audience, feedback and discussion:
While I wish that all non halachic Jews would either commit to Halacha or stop affiliating as Jews, I cannot refute the fact that historically (pre second temple, surely) they can stake a claim to Judaism.
For me, though, religion is completely institutional. Torah Truths are not objective, historical or ontological truths. They are "truths that we accept because they have value religiously". Halacha is crucial because it IS JUDAISM, bc Judaism is institutional and halacha defines the institutions. I think that our modern halachic system lacks the balls to impress anyone or effectively regulate life, but I follow it, bc it is Judaism. It should be different, we should be creating halachot, takanot, gezerot and ignoring all sorts of halachot that do not apply to our times (like our ancestors did with sacrifices etc.)
Sounds reform? Wrong. Reform and Conservative Judaism are concerned with making life easier, more comfortable and more accessible to non committed Jews. I am strongly against that. I don't want anyone who is not committed to be Jewish at all! Think about it this way: If all of world Jewry committed to halacha, we could regrow Halacha. We could have a real Torah sh'b'al Peh that would be relevant and sustainable in our 2015 reality, instead of having an "oral" Canon based in Babylonia 2 millennia ago. Haredim would protest, you say? Even YU might not accept it? Who cares, we would be a majority by 90%!
That was the vision of Proff. Leibowitz. A halacha that actually addresses our life. He had the best answer to the women in Halacha question: Halacha as discussed in Talmud and codified in Rambam and Shulchan Aruch is not aware of and never addresses modern women of today who go out in public, go to university and have professional careers. Therefore it is as if halacha discusses the kashrus of an animal that is almost extinct. Sure, if we find that animal we can apply the relevant halachos, but those halachos are irrelevant to the vast majority of animals. Same thing here. Most women today are not the same 'woman' that is discussed in halacha and so those halachos do not apply, unless we are talking about in Meah Shearim. (Obviously nidda still applies to all women bc all women still menstruate). Therefore, the halachot don't need to be changed, they need to be written in the first place! And so on for many areas of our lives today that Halacha does not touch.
But, all that said, we do still have a functioning Halacha and in it, Judaism lives. To me Judaism IS (Halachic, or) Rabbinic Judaism because it is the only kind that takes Judaism seriously and not just as a social services organization. So, the other denominations are no different to me than Karaism or Christianity (but even Chabad messianism is Judaism because they keep halacha. Again, many Chassidim and kabbalists are not monotheists strictly speaking , and they may call me a deist or an apikorus, but we are both following the same religion) It's not the beliefs that matter, it's the practice.
True,the Rambam wrote off Jews who believed in the corporeality of God as pagans with no share in the world to come, but I'm speaking here historically. Halacha is the only way in the past 2000 years to define Judaism. Otherwise we are left with a he says, he says game of who has the "real beliefs")
There is a lot to say about this. So let's go.
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