Photo Credit: Ya'akov via Wikimedia
Rabbi Shlomo Aviner

In January 2017, a serious measles outbreak in the Los Angeles Orthodox Jewish community was blamed on parents’ failure to vaccinate their children. The debate over vaccination has apparently been raging in the Orthodox Jewish community in the US, the UK, and in Israel, and we may be seeing the beginning of what happens when small children are not vaccinated: they become sick and infect other children.

In searching for a proper halachic authority on the debate which has involved Orthodox and Haredi rabbis–with and without access to medical knowledge, we discovered a Q&A that was conducted a few years ago at Yeshurun Central Synagogue in Jerusalem, with Rabbi Shlomo Chaim Hacohen Aviner, Dean of the Ateret Yerushalayim yeshiva (formerly known as Ateret Cohanim), town Rabbi of Bet El in Samaria, and an important spiritual leader of the Religious Zionist movement.


The discussion was regarding the Swine flu vaccine, which the Israeli health ministry offers free of charge every winter to the elderly and to other at-risk populations. The question was: is the rabbi for or against the swine flu vaccine?

We liked Rabbi Aviner’s answer from the start, because he established the fundamental halachic view that “this is not a question for rabbis. Rabbis are not doctors.

“We greatly appreciate the doctors, who do holy work – in the words of Maimonides in Sh’mona Prakim (Eight Chapters): rabbis are not doctors but engage in a different holy work, not medicine for the body but for the soul, which is higher than the body. Therefore, in medical matters please ask the doctors. As it is written in the Torah, ‘And he shall heal,’ and the sages say: ‘Hence we learn that the doctor was given permission to heal.'”

Next, Rabbi Aviner examined the various arguments against vaccinations from a halachic point of view. The first argument: “There are doctors who are in favor of the vaccine, but some are against it. So how do we know what to do? Maybe everyone will choose as he sees fit? And maybe it is better not to be vaccinated, because [in cases of a dispute] it is preferable to practice ‘shev v’al ta’aseh’ (sit and do nothing).”

Rabbi Aviner answered: “Just as in a dispute between rabbis we follow the majority, we do the same in a dispute between doctors. For example, if there are doctors who say that the patient should desecrate Shabbat or eat on Yom Kippur, and some say that he should not, the Shulchan Aruch concludes that we must follow the majority of doctors. In our case, this is not a majority versus a minority, but almost all of the doctors versus a few individuals, a thousand to one, and not only doctors in Israel, but also in Europe, America and in the World Health Organization (WHO).”

Second argument: “I have heard that the flu vaccines are dangerous, and in the past have caused dozens of people to suffer serious side effects.”

Answer: “True, but tens of millions have been vaccinated without any side effects, and they were saved from mortal danger. After all, halacha follows the majority. And in this case it is no longer a majority of one to a thousand but a majority of one to a million. Moreover, nearly thirty years have passed since then, and medicine has gained considerable experience in the field of flu vaccination, and by now no [new] problem has been identified in connection to the swine flu vaccine. On the other hand, many [unvaccinated] people have died of this flu, including in our own country—where several dozen have died. In any case, we follow the majority and do not conduct our lives based on the unusual and to exceptional.”

Third argument: “If a person is healthy now, why should he put himself in danger, even a remote one, in order to save himself from a danger that currently does not exist and may only appear in the future?”

Answer: “First of all, we said that this vaccine is not a distant danger, but a danger that is considered halachically negligible. But this argument does not refer specifically to the swine flu vaccine, it refers to every vaccine. In fact, all these claims also relate to every vaccine.

“Rabbi Israel Lifshitz, the author of the Tiferet Yisrael on Mishnayot (Yoma 68b), has already discussed this with regard to the inoculation against smallpox. He proves from several Gemara issues that it is permissible for a person to put himself in a low risk of one to one thousand in order to save himself from a high risk in the future, and as mentioned above, the swine flu poses a serious risk. Therefore, the high-risk groups that the doctors have indicated should not treat [vaccination] lightly.”

Fourth argument: “The Master of the universe created the human body strong and healthy and it can overcome on its own all kinds of diseases, provided that it is healthy, and we do not need to put inside it artificial things from the outside. It has a surprising vitality and will prevail over everything.”

Answer: “Of course, this claim is already beyond the scope of the flu vaccine and vaccines in general, but it undermines modern medicine. […] In a decision between new medicine and old medicine, according to Jewish law, one must follow the doctor of one’s own time, which we learn by kal va’chomer (argumentum a fortiori) from the obligation to consult the wise man in your days, as it is written, ‘And you shall come to the judge who will be in those days’ – kal va’chomer doctors, since medicine is developing. Many things have been proven and many have been refuted, there are new means of research, there are statistical tools that make it possible to distinguish between an anecdotal phenomenon and an overall phenomenon, and so on and so forth.”

Fifth argument: “In general, one must believe in God and in Divine Providence. If God decreed that I would be healthy, I do not need doctors, and if God decreed that I would be ill, all the doctors would not help. You need faith and confidence and that’s what will heal you, and not going to doctors.”

Answer: “You asked a nice question. Maimonides has already answered this in his commentary on Mishna Pesachim, that according to your logic we should say: Don’t eat. If God decrees that you die, you will die even if you eat. And if God decreed that you’ll live, you will live even if you don’t eat. Conclusion: Do not eat.

“Of course, it’s nonsense. Naturally, God does everything, but He does so through His messengers, including angels of harm, such as bacteria, and also ministering angels, such as doctors. And if you refuse the help of the good messengers of God, you deserve punishment, and the punishment may be that the ministering angels will abandon you, and the angels of harm will harm you. As explained at length in Sefer Mesilat Yesharim chapter 9.”

In conclusion, Rabbi Aviner said, “This is the rule that emerges from everything I said: my friends, do what the doctors tell you and do not consider yourself to be a doctor. We very much value independent and critical thinking, but we also need some common sense and humility.

“Therefore, my dear friends, go to the mainstream doctors who are around today, and may you be blessed with good and long lives.”