Many have recently asked whether we can immerse our keilim in a river. While this might be an option for Ashkenazic Jews in an extreme circumstance, it is never an option for a Sephardic Jew. Let us explain why.
Differences between a Mikva and a Maayan
The rules of constructing a Mikva emerge from a Pasuk (Vayikrah 11:36) that Chazal interpret as presenting two modes of ritual purification. One is immersion in a Maayan (natural spring, such as the celebrated spring of the Ari z”l in Tzfat) the second is immersion in a Bor Mikva Mayim, a pit that contains a collection of rainwater. We refer to a Bor Mikva Mayim simply as a Mikva.
There is a major difference between a Mikva and a Maayan. A Maayan is effective even though it is running water but a Mikva, must be stationary (or Ashboren in the language of Chazal, Mikvaot 1:7-8).
Zochelin versus Ashboren
We are extremely careful regarding the requirement that Mikva water be stationary. The Rama (Y.D. 201:2) rules that a Mikva that is not stationary is disqualified on a biblical level (this is agreed to by virtually all authorities; see Encyclopedia Talmudit 12:20-21). Almost all Rishonim believe that the water need not be flowing in a torrent in order to be considered Zochlin. Even water flowing through a crack in the wall of the Mikva is defined as Zochlin.
Rivers
Thus, one may immerse in a spring even if it is flowing but that we are prohibited from immersing in a collection of rainwater (Mikva) if the water is flowing. The Amoraim and Rishonim, though, debate the status of a river. Many rivers consist of a combination of rainwater and underground springs. The question, accordingly, is whether we regard rivers as a Mikva and they are thus disqualified for immersion because they are not stationary or do we regard them as Maayanot and are acceptable even though they flow.
This debate has never fully been resolved. Shmuel (Shabbat 65b) adopts a very straightforward approach. If the majority of the river consists of rainwater, then the river is regarded as a Mikva. If the majority of the river is from underground springs then its status is that of a Maayan. This very apparent in the rivers during a drought year when they appear significantly lower than normal. The impact of the rain (or lack thereof) on the rivers is quite evident.
On the other hand, Shmuel is quoted (ibid.) as adopting a contradictory view. He is quoted as saying a somewhat enigmatic statement “Nahara Mikipei Mivrach.” Tosafot (ibid. s.v.Deamar Shmuel) explains that Shmuel means that the primary source of a river is its underground sources. Tosafot explain, based on the Gemara (Taanit 25b), that for every handbreadth of rain that falls into the river, another two handbreadths of water emerge from the underground water sources. This version of Shmuel believes that all rivers are defined as a Maayan. The Rama (Hilchot Mikvaot 201:2), though, cautions that even this opinion concedes that if the river consists entirely of rainwater then it is not a Maayan. If a river or stream dries up completely when there is a drought, then it is obvious, notes the Rama, that this river is simply a flow of rainwater (Chardalit Shel Geshamim), which all Rishonim agree is not a Maayan (see Mikvaot 5:6).
The Rishonim debate which opinion to follow. Most Rishonim follow the stricter approach of Shmuel to follow the majority of the rivers’ water content. These Rishonim include the Rambam (Hilchot Mikvaot 9:13), the Tur (Y.D.201), and the Ramban (in his commentary to Shabbat 65b). Tosafot (ibid.), however, cite Rabbeinu Tam who rules in accordance with the lenient version of Shmuel. Tosafot conclude “it is upon this we rely to immerse in rivers, even if they are quite swollen.”
Rav Yosef Karo (Shulhan Aruch Y.D. 201:2) rules in accordance with the stricter opinion. The Rama (ibid.), though, records the practice to immerse in rivers when a community is far from a Mikva. The Rama concludes that it is quite preferable to follow the strict opinion, but that one should not admonish those who follow the lenient opinion. The Aruch Hashulhan (Y.D. 201:42) notes that in the late nineteenth century the practice of those who live at a great distance from a Mikva was to immerse in a river.
Conclusion
Great rabbinic authorities have debated immersing Keilim in a river for nearly two thousand years. While Ashkenazic Jews might be permitted to rely on the lenient opinions of Rabbeinu Tam and the Rama on an extreme circumstance, Sephardic Jews always follow the stricter view of the Rambam and Shulhan Aruch that it is never a permitted option.
Regarding an ocean, however, all agree that one may conduct Tevilat Keilim in an ocean since the Torah describes the oceans as a Mikvah (Bereishit 1:10) וּלְמִקְוֵה הַמַּיִם קָרָא יַמִּים.
Rabbi Haim Jachter is the spiritual leader of Congregation Shaarei Orah, the Sephardic Congregation of Teaneck. He also serves as a rebbe at Torah Academy of Bergen County and a dayan on the Beth Din of Elizabeth.