Sometimes, life imitates Torah.

First, this week’s Torah portion. It is one of the all-time favorites from the book of Leviticus — Tazria. It describes various diseases and how it was the responsibility of the priest to diagnose and quarantine those who suffer from those illnesses. The term that appears, repeatedly, is nega — plague.

Second, the rapidly approaching festival of Pesach — complete with the seder’s recitation of the ten plagues that fell upon Egypt.

Time to talk about a new/old plague — the plague of measles, that is now rampant in certain communities in Rockland County, in upstate New York.

Erica Wingate was working at a clothing store in town this week when a male customer, with the black hat and sidelocks typically worn by ultra-Orthodox Jews, started coughing.

Another shopper standing next to him suddenly dropped the item she had been holding and clutched her child. “She was buying something, and she just threw it down,” Ms. Wingate recalled. “She said, ‘Let’s go, let’s go! Jews don’t have shots!’”

A measles outbreak in this suburban New York county has sickened scores of people and alarmed public health experts who fear it may be a harbinger of the growing influence of the anti-vaccine movement. But it has also intensified long-smoldering tensions between the rapidly expanding and insular ultra-Orthodox Jewish community and secular society.

The authorities here in Rockland County have traced the spread of measles to ultra-Orthodox families whose children have not been vaccinated.

Rockland County has barred unvaccinated minors from public places. Since October, there have been 153 confirmed cases of measles. In fact, measles cases are at the second greatest number of cases reported in the United States since measles was declared eliminated in 2000.

Why is this happening? Because there are ultra-Orthodox Jews who don’t believe in vaccination.

I have vast respect for the Orthodox community, and I count various haredi rabbis and teachers among those who have influenced my own thinking.

Therefore, I write these words with sadness and great pain.

The willful refusal to vaccinate children is against Jewish law, teachings — and even a violation of Jewish memory.

Here is how I see it.

• To heal someone — or yourself — is a mitzvah (a religious obligation). Rabbi Abraham Joshua Heschel wrote: “Medicine is prayer in the form of a deed. The act of healing is the highest form of the imitation of God.”
• You are not allowed to endanger yourself needlessly. The Shulchan Arukh, the classic code of Jewish law, says: “Wherever there is a potentially life-endangering pitfall or obstacle, it is a positive commandment to remove it … as the Torah says: “Guard yourself and guard your soul.” (Deuteronomy 4:9-10).
• The availability of medical care is a public good. If you live in a religious culture that venerates the great Maimonides, you must remember that he was, first and foremost, a physician who saw his work as a healer as the most important calling in his life.
• Judaism does not know about parental rights, as it does not really believe in rights. Judaism believes in responsibility. The Talmud says Jewish parents are obligated to teach their children three things: Torah, a trade, and how to swim. “Swimming” is a metaphor. Parents need to teach their children how to avoid dangerous situations. Like, for example, infectious diseases.

There is a story in the Talmud about two men in a rowboat. One starts drilling under his seat. The other protests loudly. But the “driller” responds: “I am only drilling underneath my seat.” In society, when we drill under our own seat, everyone drowns.

In that spirit, consider a December statement signed by more than 40 Bergen County, N.J. rabbis and Orthodox school officials that says that Jewish law commands vaccination:

Vaccination is not only an obligation to protect the health of our children and ourselves, but a responsibility we have towards others…Those who do not vaccinate can potentially spread life-threatening diseases to others who are vulnerable. We strongly urge all parents to vaccinate their children as recommended by the American Academy of Pediatrics.

There is one last thing that I need to say here.

I would be the first to scream about possible antisemitism that emerges from this situation — and from any situation.

The ultra-Orthodox community has an obligation to actively prevent, and therefore avoid, any situation that would result in such slurs as “Let’s go, let’s go! Jews don’t have shots!’”

This is an echo of an ancient anti-semitic libel against the Jews — that they are spreaders of plague.

It was among the first anti-semitic accusations in history. The ancient Egyptian grammarian, Apion, believed that the Egyptians actually expelled the Jews from their land because they were lepers. The ancient Jewish historian, Josephus, wrote a work contradicting this theory.

Not to mention the slur against the Jews in medieval times — that they started the cataclysmic Black Death by poisoning the wells of Europe.

Jews need to be sensitive to this history.

Especially now — when anti-semitism is becoming its own plague, emerging both from the Left and the Right.

To do anything that would further anti-semitic accusations would be…

Well, let me use the Yiddish term that ultra-Orthodox Jews would know very well…

Shanda fur die goyim.

An elegant translation: This creates the danger of a shameful situation that will have negative ramifications on our relationships with the gentiles, in whose midst we live.

Or, let’s put it on a positive note.

“Love your neighbor as yourself” is also in Leviticus.

These are your neighbors.

Mipnei darkhei shalom, in the interest of peace — vaccinate your children.