Judaism is constantly changing and developing, a process that includes dropping untenable practices or manufacturing ways around them, adding new rituals, and investing old rituals with new meaning.
The Judaism of the Torah is not the Judaism of the Mishna. In fact by the time of the Mishna, Judaism had split into several sects, only one of which survived. The winning sect, Phariseeism, which transitioned into Rabbinic Judaism, is popularly considered the authentic Judaism, but the whole idea of authenticity is a fallacy. There is no authentic Jewish condition, only the condition that obtains at the moment.
Ironically, the word Pharisee shows this to be true. It comes from the word פָּרוּשׁ pārûsh, meaning “set apart". Religions develop sects, as new groups find reasons to set themselves apart.
Had the Pharisees came first, it seems unlikely that they would have acquired this name.
Meanwhile, their main rivals, the Sadducees have a name derived from the word for "to be correct". (Think about what happened in the 19th century. The "new" Jews called themselves "reformers", while the "old" Jews were called "conservative" or "orthodox", even as they developed new sects, in part, as a response to the reform. The Pharisees are called "set apart"; their main rivals are called "correct." So who broke away from who?)
Though the Pharisees won the first battle we know about, history didn't end with their victory. Judaism continued to change and new sects developed, including Judeo-Christianity (which transitioned into Christianity) Karaism, Hasidut, and the three responses to modernity namely Orthodox, Conservative and Reform Judaism. Additional sub-sects exist within Hasidut and Orthodox Judaism. And each sect contributed to the changes Judaism has undergone.
Demonstrating that these changes have occurred, and that our current day interpretation of Judaism is not simpicato with the plain Scripture is like shooting fish in a barrel.
Consider the frum shabbos which requires cholent, kugel, zmirot and a nap. Where is that represented in the Chumash? And where, for that matter, are the sacrifices the Chumash says must accompany every festival? Does any frum Pesach require the sacrifice of a goat or a sheep? More to the point, does any frum person really think his Pesach insufficient for not having included a blood sacrifice? (Made impossible by the loss of the Temple, you say? To which I reply: See what I mean about Judaism changing?)
Moreover, the Bible makes no mention of Lag B'omer, or upshurim, or g'broks, or any ritual clothing other than tzitzis. The Bible's Shavuos is a harvest festival, not the fulfilment of Pesach or the day the Torah was revealed. Another pillar of Judaism as we understand it is monotheism, but the Bible, notably the Ten Commandments ("No other God before Me") is, in many places, monolatrist.
None of this should be construed to mean that I think modern forms of Judaism are illegitimate. Quite the contrary. Judaism has always been nothing more and nothing less than what Jews say it is. How we decide which speakers and statements matter is outside the scope of this short blog post, but there can be no doubt that Judaism changes as Jews, as a whole and as specific sects, continue to think and speak about it. And we can expect such morphing, developing, changing and evolving to continue as long as there are Jews who take Judaism seriously.
A comment in which I said this in different words:
Lo Tignov means whatever the Rabbis say it means. And I mean the Rabbis in every generation, with the support of the people. Together they create the limitations applications and exceptions and interpret all that back into the verse. [Machlokes rishonim as to what midrash halacha is by the way]
I agree no one says we're allowed to steal, but you already have many Jews who will say that many things "aren't really stealing." And come back in 2000 or 10000 years and who knows what we'll find. Jews from 3000 years ago would be shocked to see how blithely and cavalierly we ignore the black and white laws of ritual impurity. If you were to return 3000 years from now, you'll be shocked at how Judaism has changed, too - if Judaism has survived. We just don't know what will be doing the shocking.
Another point: Christians consider themselves the true Israel, and the legitimate inheritors of the bible tradition, yet they have manufactured ways to ignore huge swaths of the bible. Perhaps future Jews will do the same (more than we have done so already, I mean)
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