Sam Lehman-Wilzig
Prof. Sam: Academic Pundit

Science, Halakha, and Homosexuality

Some of Israel’s leading ultra-Orthodox and Orthodox rabbis have lately attacked homosexuality in very aggressive terms. Indeed, with Israeli society replete with all sorts of halakhic (Jewish Law) offences e.g., theft, murder, adultery, Sabbath transgressions (plural), the question needs to be asked: why pick on the offence of homosexuality? My answer: this issue is far more dangerous to the traditional (“Orthodox”) belief system than almost all other Jewish law violations because it threatens to undermine the entire structure of Torah infallibility.

The problem is “science.” Many philosophers, theologians, and sociologists have tried to argue that there is no inherent conflict between religious belief and science. They are wrong – and homosexuality is the classic case showing just why (it bears noting that Christianity and Islam have almost identical, strict prohibitions regarding the issue). As opposed to strictures against such transgressions as adultery, theft etc., whose basis is exclusively moral (and perhaps sociological too), the (im)morality of homosexuality has to contend with a strong scientific, counterfactual basis. Put simply, modern science provides an empirical basis for the biology and pervasiveness of homosexuality.

But what to do if the Torah seems to explicitly forbid such sexual relations? Is the only choice for the Orthodox to ignore the science of sex and sexual preference? That’s problematic because the same science that studies homosexuality is the science that has brought us modern medicine, technology, and so on, on which the Orthodox also base their lives. The “logical” result: for the true believer, science in general is dangerous. If you want to know why the “Core Curriculum” is not taught in haredi schools, here is the basic reason: not the science of homosexuality specifically but science in general will ultimately undermine religious belief as the two clash on this (and several other) central issues of contemporary life.

What has “science” discovered regarding homosexuality? That it is found in every society on Earth, notwithstanding the huge racial, ethnic, cultural, economic etc. etc. differences between peoples. Thus, something so “universal” – despite the huge variance between societies – cannot be a matter of culture or any other “social” factor; rather, it is ingrained in human biology. Moreover, as the Scholarly Community Encyclopedia states: “There is now a large body of research evidence that indicates that being gay, lesbian or bisexual is compatible with normal mental health and social adjustment” ( It is also now clear that homosexuality is found among many animal species. Of course, that’s not proof that it is “moral,” but such prevalence further underscores its biological basis, as animals aren’t “influenced” by social mores or “ideology.”

For the true believer, homosexuality’s scientific challenge doesn’t end there. Lesbianism is as widespread as male homosexuality (albeit in somewhat lower percentages) – but the halakha doesn’t seem to be aware of that, as there is no prohibition against female homosexuality! Why would that be so? Here the answer can be found in a specific term appearing in many prayers and biblical verses, the key word being zerah (male “seed” i.e., sperm), as when God blessed Abraham (Genesis 22:18): “And in thy seed shall all the nations of the earth be blessed; because you have hearkened to My voice. The Bible had no conception (pun intended) that conceiving a baby had two “parents”: sperm and ovum. Thus, women were perceived as being mere vehicles (temporary incubators) of the fetus. What they did sexually outside the marital bed had no influence on bringing new life to the world; only a man “wasting his seed” could be considered biologically and morally counterproductive.

In short, modern science has shown the Bible to be scientifically (read: factually) illiterate. As the halakha cannot fight science on the latter’s empirical terms, it tends to withdraw into its own world of moral strictures, attacking as something repugnant what science has lucidly shown to be an integral part of Nature’s variety. (Parenthetically, it must be noted that many modern Orthodox are scientists in the broad sense: doctors, researchers, mathematicians and so on; their way of “dealing” with the halakhic challenge of homosexuality is to live with cognitive dissonance, splitting their mental life into two equal but unconnected parts: science on one side, Jewish tradition on the other. But that’s OK – who among us doesn’t live with some dissonance regarding some aspect of their life?)

What, if anything, can the halakha do? Actually, not much need be done because the true believers are fighting a losing cause that has already infiltrated its own bastions. The word is out from within: more and more completely normative ultra/Orthodox families have discovered that one of their dear children, untouched by “secular ideology,” is a homosexual. It is getting harder and harder to maintain the theory of “secular (ideological) infection” and ignore reality.

In truth, the halakha has several ways to potentially deal with the issue. First, the commandment speaks only of the sex act itself; it does not negate the personhood (or Jewishness) of the homosexual individual. Second, novel approaches have already emerged on the Orthodox scene e.g., marrying off a homosexual with a lesbian, together running a completely traditional, “kosher” home – bringing up children etc. (What they do in private has never been a Jewish concern; we don’t do “Inquisition”.) Eventually, given the widespread nature of the phenomenon among the Orthodox, in numbers no different than secular Jews (and the rest of the world), the Rabbis will find an “out” – as they have done with so many other “problematic” challenges in Jewish history (e.g., Jewish women suffered from rape among the Romans, so that Jewish patrilineal descent had become problematic because one couldn’t know who was the real father? Change a thousand years of patrilineal descent to matrilineal; we always know who the mother is!). Here’s a way out: a close reading of the biblical injunction against homosexual activity shows that it is found within the context of avodah zarah – idol worship. Thus, one can reasonably argue that only in that context should it be forbidden.

In short, homosexuality isn’t the real problem here; how the halakha based on Torah (and Talmudic) ignorance of the way the world really works – that’s the problem. However, I am actually optimistic because the halakha has successfully overcome stiff challenges numerous times in the past (e.g., Jubilee loan voidance, leading the rabbis to come up with the “Pruzbul” workaround). Given scientific evidence and social reality, it will ultimately find a way to accept even this “abomination.”

About the Author
Prof. Sam Lehman-Wilzig (PhD in Government, 1976; Harvard U) presently serves as Academic Head of the Communications Department at the Peres Academic Center (Rehovot). Previously, he taught at Bar-Ilan University (1977-2017), serving as: Head of the Journalism Division (1991-1996); Political Studies Department Chairman (2004-2007); and School of Communication Chairman (2014-2016). He was also Chair of the Israel Political Science Association (1997-1999). He has published five books and 69 scholarly articles on Israeli Politics; New Media & Journalism; Political Communication; the Jewish Political Tradition; the Information Society. His new book (in Hebrew, with Tali Friedman): RELIGIOUS ZIONISTS RABBIS' FREEDOM OF SPEECH: Between Halakha, Israeli Law, and Communications in Israel's Democracy (Niv Publishing, 2024). For more information about Prof. Lehman-Wilzig's publications (academic and popular), see: