MONSEY, N.Y., Sept. 6 — Since sundown on Saturday — when the Jewish Sabbath ended — men, women and children have been scrubbing kitchen counters and stoves, and dipping pots and utensils in scalding water.

“My husband and I had to leave everything we were doing,” said Esther Herzl, 61, a Hasidic grandmother who lives here, “and all we did was scrape and scrape and scrape — from the cutlery to the glassware to the countertops, oven and stove. I’m beat. We’re truly religious, so we don’t cheat in the cleaning.”

The cleansing ritual, which is prescribed by Jewish law, became necessary after a Hasidic butcher was accused of stocking the shelves of a kosher grocery store here with nonkosher chicken and selling it to thousands of Orthodox Jewish families.

Now a group of rabbis is debating the fate of the butcher.

Last week, the state’s Department of Agriculture and Markets seized 15 cases of chicken from the store, Hatzlocha Grocery, where the butcher sold chicken and other meats from rented shelf space to test it for salt, a key ingredient in kosher food.

The state agency and the rabbis, who represent several Hasidic congregations in Monsey and elsewhere in Rockland County, are trying to determine the origin of the chicken, whose package carried the stickers of two area kosher meat plants that had ceased supplying to the butcher after he failed to pay them, according to a local rabbi and an employee at the store.

“To sell nonkosher as kosher is one of the biggest acts of betrayal that a Jewish person can do to another,” said Rabbi Menachem Meir Weissmandel of Chemed Shul, a local synagogue. “This is the darkest day in the history of our community since we settled in this area many years ago.”

The butcher, Moshe Finkel, owns Shevach Meats, which buys kosher chicken and other meats in bulk, and then slices, packages and sells it at the grocery store and to wedding halls, religious schools and Hasidic camps in the Catskill Mountains.

Attempts to reach Mr. Finkel, who lives in Monsey, by telephone were unsuccessful on Wednesday. Rabbi Weissmandel said that Mr. Finkel was banned from Hatzlocha Grocery last Wednesday, as soon as the store owners uncovered his alleged transgression.

He said the store owners confronted Mr. Finkel after they noticed the shelves lined with kosher meats, even though his usual suppliers had not made a delivery. Almost immediately, leaflets lined Hatzlocha’s windows, telling patrons in Hebrew that Shevach Meats had been caught selling nonkosher chicken. At synagogues and on the street, rabbis instructed the faithful to throw out the meat and cleanse their kitchens to make them kosher again.

The matter has been the talk of Jewish Web logs. One of them, Vos Iz Neias, announced it under the banner headline “Butcher Sells Treifa Chicken as Kosher.” (Nonkosher food, or food that is not in accord with Jewish dietary laws, is called treif, which derives from the Hebrew word teref, or torn.) The posting generated 440 comments in two days.

Rabbinical panels often work in secret, so it is hard to figure out when the rabbis here will reach a decision or what it will be.

As for the state, a spokeswoman for the Agriculture Department said investigators were trying to determine if the chicken was ever certified as kosher and advertised as such at the store. She said violators are subject to fines of up to $1,000.