After the Jewish people were victorious in their war against the Midianites, Elazar the High Priest taught them the laws of “kosherizing” food utensils taken from the spoils of the enemy.1 First, vessels that came in contact with hot non-kosher foods were to be purged by fire. Then the verse instructs: “They shall be purified; indeed they shall be cleansed in the niddah waters.” This is interpreted by the Talmud2 to mean that the vessels should be purified by immersion in the waters used by a niddah for her purification—a mikvah. The verse then says that in the case of vessels that were not used with hot foods, one need only “pass them through water.” Rashi3 interprets this to mean that all vessels—including those not used with hot food—must be immersed in the mikvah.

Traces of non-kosher food can remain in a dish even when it appears to be clean. Thus the function of the initial cleansing by fire (or hot water, depending on how it was used) is to remove any such remnants of forbidden food. The immersion of the vessel in a mikvah, however, serves a different purpose. The reason for this immersion is to bring the vessel into the holy domain of the Jewish people.4 When a food utensil is in the possession of a non-Jew, in addition to the fact that it is presumably used for non-kosher food, it also acquires a spiritual impurity as a result of being in a potentially non-kosher state. When it is purchased by a Jew, who will from now on (presumably) use it only for kosher food, it needs a ritual cleansing to remove the impurity brought about by the potential use of the vessel for non-kosher food.5

For this reason, the law of immersion of vessels applies even when one purchases new, never-used food utensils from a non-Jew. Of course, if they were used, they must first be “kosherized” (see Koshering Appliances and Utensils), and only afterwards should they be immersed in a mikvah.6

Which Utensils?

  • The obligation to immerse utensils purchased from a non-Jew applies to all metal and glass utensils.7
  • Wooden utensils or stoneware need not be immersed.
  • China or ceramics that are glazed should be immersed without a blessing (see below).
  • There are differing opinions as to whether or not plastic vessels need to be immersed.8 The majority opinion seems to be that they need not be immersed. One who does immerse them should not recite a blessing.
  • If a vessel is made of several materials, some of which require immersion (e.g., metal or glass) and some of which do not (e.g., wood), the following rules apply: 1) If the vessel is mostly made of metal or glass, even if it is held together by wood, one should immerse it with a blessing.9 2) If the vessel is mostly made of wood, but is held together by metal or glass, one should immerse it without a blessing.10 3) If the vessel is made completely of wood, but has a decoration (or the like) made of metal, it need not be immersed at all.11

Disposable Utensils

If a (metal) utensil is disposable, it need not be immersed. If one plans on reusing the utensil, but it is not durable enough to be used on a permanent basis, some say they need not be immersed, others disagree.12

There is no halachic basis for the common misconception that non-disposable utensils may be used once without immersion.13

Definition of Utensils Used for Food

  • The obligation to immerse utensils applies only to utensils used for food preparation, serving or eating14 that touch the food directly.
  • The obligation to immerse vessels also applies to electrical appliances used in food preparation that touch the food directly (for example: a toaster, deep fryer, George Foreman Grill, or electric kettle).
    Experience has shown that electric appliances can be safely immersed if, after the immersion, one allows them to dry for three days before plugging them in. To speed up this process, one can direct a fan at the area of the motor.
  • If the utensil is used in the food preparation, but not in the final steps of preparation, the vessel should be immersed without a blessing.15 Some examples of this would be kneading bowls, a coffee grinder, and a knife used to carve only raw meat.
  • Any utensil that does not come in contact with the food (for example, a corkscrew) need not be immersed.16

Definition of Utensils Owned by a Gentile

  • If a utensil was made by non-Jewish workers in a Jewish-owned factory, no immersion is needed.17
  • If a utensil was made by Jewish workers in a factory owned by non-Jews, the utensil must be immersed.18
  • If the company that manufactured the utensil is owned jointly by Jews and non-Jews, the utensil must be immersed, but a blessing should not be recited.19 For this reason, a utensil purchased from a public company should be immersed without a blessing. Presumably, some of the shareholders are Jewish, which would include it in the above rule.
  • If, at any time before reaching the consumer, the utensil was owned by a company whose sole owner (or owners) was not Jewish, the vessel should be immersed, and a blessing should be made.20

What Mikvah Is Kosher for This Purpose?

  • In order to fulfill the obligation of immersing vessels, one must immerse them in a kosher mikvah. By definition, any mikvah that is kosher for use by women is kosher for immersing vessels.
  • Any natural, stationary body of water is considered a kosher mikvah. This includes lakes and the ocean.
  • Ordinary rivers should not be used, as flowing rainwater does not constitute a kosher mikvah. Rivers that originate from a spring are kosher for immersion, but only as long as there is no significant addition of rainwater. For this reason, it is best to refrain from using a river for immersion unless one is near the actual spring from which it originates.21
  • A swimming pool or any other man-made body of water may not be used for immersing vessels.
  • Whether or not a mikvah built specifically for use by men is kosher for immersing vessels depends on how it was made.22
  • In many communities a special mikvah designated for immersing vessels is built separately, in order to allow easy access for those wishing to immerse the vessels while keeping the regular mikvah clean.
  • If there is no other mikvah readily available, one may immerse a glass vessel in a large snowdrift.23 However, one should not do this for a metal vessel.

Before Immersion

It is forbidden to use utensils requiring immersion before immersing them.24 If one did prepare food in such utensils, the food is not forbidden,25 but it must be removed from those vessels as soon as one realizes26 the error. The utensil must be immersed no matter how many times it was used without immersion.

Who May Immerse

One need not bear in mind any special intention during the immersion. For this reason, this mitzvah may be performed by a child. In addition, if a Jew makes the blessing and immerses at least one item, he may allow a non-Jew to immerse the rest of the vessels. In such cases, however, a Jewish adult must supervise to make sure the immersion was done properly.27

Preparing the Vessel for the Immersion

In order for the immersion to be valid, no intervening substances may be found on the item being immersed. For this reason, one must make sure to remove all labels or any rust, etc., before immersing the vessel. The sticky glue left behind from stickers must also be removed. (Eucalyptus oil is good for this.) If the sticker is meant to be left on the item—for example, care instructions—it need not be removed.28

The Blessing

Before immersing the vessel, one should recite the blessing: Baruch atah . . . asher kidshanu . . . al tevilat keli [or kelim for more than one vessel].

The English translation is: Blessed are You, L‑rd our G‑d, King of the Universe, Who has sanctified us with His commandments, and commanded us concerning the immersion of a vessel [or vessels].

This blessing may not be made in the room of a mikvah in which people immerse, as this area has the status of a bathhouse in which blessings may not be recited.29 If one is immersing vessels in such a mikvah, he may recite the blessing while standing outside the mikvah area, then walk in and start the immersion. The walking between the recitation of the blessing and the beginning of the mitzvah is not considered an interruption, because it is necessary for the immersion.30

Please note: Many types of utensils must be immersed without a blessing (see above). If one is immersing many utensils, some of which require a blessing and some of which do not, one should recite the blessing, immerse those utensils that require a blessing first, and then immerse the rest of the utensils. It is best to immerse such vessels together, so that the blessing will include the items that do not require a blessing.31

How to Immerse the Vessels

  • The blessing should be recited before beginning the immersions.
  • The utensil should be completely immersed in the mikvah.
  • All handles of the utensil must also be immersed.32
  • While the utensil is submerged, one should move the hand with which one is holding the utensil from one spot on the utensil to another. Alternately, one can switch hands. This is to allow the water to reach the entire utensil.33
  • Some authorities say that if the utensil is held loosely, this is sufficient.34
  • One may place several utensils on a tray and immerse them simultaneously. Silverware may be placed in a mesh bag and immersed.35 If there are many pieces of silverware in the bag, the bag should be agitated under the water to allow the water to reach all of the surfaces of all of the items.
  • If one is immersing various utensils, he should not speak between immersions unless it is pertinent to the immersion. Nevertheless, if he did talk, he need not make another blessing.36
  • It is only necessary to immerse each item once.37

Utensils That Cannot Be Immersed

  • If an item is too large to immerse, or it would be ruined through immersion, one should take it apart or otherwise break it, and then put it back together or fix it. When one does this, it is considered as if the utensil has been “manufactured by a Jew.”38 If one cannot do this, he should give the utensil to a non-Jew as a gift and then “borrow” it back from him for extended (indefinite) use.39 The non-Jew should acquire the utensil in a halachic sense by picking up or moving it.40
  • The same can be done for ordinary utensils in a place where there is no mikvah available for immersing vessels.41
  • If one was initially unable to immerse a vessel and had to rely on the abovementioned alternative solution, he should still immerse it when he comes to an area that has a mikvah.42

Immersion on Shabbat and Yom Tov

One may not immerse utensils in a mikvah on Shabbat or major holiday.43

If it is already Shabbat or the holiday and one needs to use the utensil, one may give it to a non-Jew and “borrow” it back, as explained above. After Shabbat it must be immersed.44

After Passover

Even if one sold one’s utensils to a non-Jew for the duration of Passover, he does not need to immerse them again when buying them back after Passover. Although the sale to the non-Jew was legally binding, there was no real possibility that he would actually use the items.45