Growing up in a heavily Jewish (but not very Orthodox) suburb in the US, the answer seemed simple enough: Jewish culture could be expressed by peppering your conversations with Yiddish, eating “Jewish” food like gefilte fish and kishke, and knowing the lyrics to at least two or three songs from Fiddler on the Roof.

And it made sense. After all, these were the things that bound the Jewish people I knew and saw, including both Holocaust survivors and first-generation Americans, who had grown up in the slums that absorbed millions of Jewish immigrants in the early decades of the 20th century.

But it was not so simple.

I grew up, traveled a bit, and encountered Jewish people different from those I’d grown up with. Sephardim were Jewish, no doubt about that, but they did not speak a word of Yiddish. And come to think of it, neither do my very Ashkenazi (7th-generation American) children. And neither does the food thing hold true anymore. After all, you’d not catch a card-carrying Moroccan Jew dead with a piece of gefilte fish on his plate. And neither would my kids know what to do with that limp piece of white stuff that looks like tofu but smells like fish (which it is, of course).

And you do not need to do much thinking to conclude that Fiddler on the Roof cannot be the be-all-and-end-all arbiter of Jewish culture, which existed for thousands of years before Broadway and will continue to exist long after theater is forgotten.

So what is it that defines Jewish culture?

For that matter, what is it that unites Jewish people? Is it common DNA? That can’t be it, since plenty of Jews—including converts—have different DNA than the rest of us.

And we already established that it’s not language, food, or country of origin.

The answer, I have learned to believe, is the only thing that is the common heritage of every single Jewish person: The Torah.

Keeping Shabbat, that’s Jewish culture. Whether you honor Shabbat with gefilte fish or with peshkado frito (the fried Shabbat fish prized by generations of Sephardic Jews) is secondary.

Being scrupulously honest in your dealings and giving (at least) 10% of your earnings to worthy causes is authentic Jewish culture.

Jewish holidays, tefillin, kosher food, Torah study — these are the things that all Jews share. It’s remarkable to consider that the tefillin of a Yemenite Jew and those of a Danish Jew are almost identical, with the differences so small that the casual onlooker would not spot them.

Millennia of exile have changed and influenced our language, our food, our place of residence, and so many elements of what we’d call our culture.

But Torah has remained our rock, our rallying point, and the one piece of Jewish culture that will never leave us. It’s our culture, our soul, and our Divine heritage.