by R. Gil Student
I. Ferries on Shabbos
There have been times in history when Jewish communities have settled on different sides of a river. The question arose whether people could cross the river on Shabbos. Of course, if there is a bridge that you can walk across then the issue is fairly simple. As long as you don’t travel outside the techum Shabbos (roughly 6/10 of a mile from the boundary), there isn’t a problem. However, bridges can be expensive. Small towns might use other options that raise halakhic questions.
In the following discussion, we will distinguish between a floating bridge, a ferry and a reaction ferry. A floating bridge is a series of connecting boats or floats that serve as a bridge that you can walk across. The floats are connected to each other and connected to each side of the river. A normal bridge reaches over the river and does not obstruct water traffic. A floating bridge blocks traffic.
A ferry is a boat that is manually driven back and forth across the river, from side to side. In contrast, a reaction ferry is connected by cable to each side of the river and floats from side to side. Primarily, the reaction ferry is propelled by the water current but may be steered or pushed by a driver. It barely requires any human intervention. Which, if any of these, may be used on Shabbos to cross the river?
II. Riding Boats on Shabbos
Rosh (R. Asher Ben Yechiel, 14th cen., Germany-Spain; Eruvin 4:3) discusses whether it is permissible to travel on a riverboat that departs on Shabbos. He quotes Rashbam (R. Shmuel Ben Meir, 12th cen., France; Tosafos, Eruvin 43a, s.v. halakhah) who permits boarding a boat on Shabbos that will depart on that day. While the Gemara (Shabbos 19a) says that you may not set sail even three days before Shabbos (except for a mitzvah), Rashbam says that this passage follows Beis Shammai while we follow Beis Hillel. Tosafos (ibid.) quote Ri (R. Yitzchak of Dampierre, 12th cen., France) who strongly disagrees. Rosh disagrees as well. Rather, the Sages forbade sailing on the sea because of the motion sickness and general lack of comfort (Rosh, Shabbos 1:38) and that applies also to sailing on a river.
Ran (R. Nissim Ben Reuven, 14th cen., Spain; Commentary on Rif, Shabbos 7a-b) quotes Ramban who says that it is forbidden to sail because the sailors will violate Shabbos on your behalf (or it will look like they are doing so). Therefore, if most of the passengers are gentiles, it should be permissible. However, there is still a problem of techum, leaving the boundary of your Shabbos area. To solve this, Ran says that the practice is to establish residency on a boat as Shabbos begins — even lighting candles on the boat — and then returning the next day to travel on the boat. In this way, they do not violate the techum (boundary) of Shabbos because their techum is on the boat. Rosh argues that this accomplishes nothing because they still violate the rabbinic prohibition of setting sail on Shabbos.
Rav Moshe Isserles (Rema, 16th cen., Poland; Shulchan Arukh, Orach Chaim 248:3) says that some follow the Ran by establishing residency on the boat and then boarding on Shabbos day. He rules that we should not object to this practice.
III. Ferries on Shabbos
In 1606, Rav Mordechai Ziskind Rotenberg (Maharam Ziskind) was asked about a community in which a small river split the town. When the town’s bridge broke, they established a reaction ferry in which the sailor moves the boat only by pulling on the cable that spans across the river. Can the few Jews on one side of the river use the ferry on Shabbos to go to shul? The ferry is the only way they can pray with a minyan. Maharam Ziskind says that according to the Ran, this should be permitted even without establishing residency on the boat because the travel is completely within the techum of a small town. However, he declines to permit this practice because Rema does not endorse this view but rather just says not to object if people follow it. Additionally, he suggests that the reason to establish residency on the boat is not to move your techum to the boat. Rather, it is because once you establish your residency on the boat, when you return to the boat on Shabbos day, you are entering your “house”. Therefore, you would need to light Shabbos candles on the ferry and then return during the day.
Additionally, Maharam Ziskind says that this would only be allowed in order to do a mitzvah. However, he quotes Rav Ya’akov Moelin (Maharil, 15th cen., Germany; Eruvin, par. 7) who astonishingly says that going to shul is not a sufficient mitzvah to allow making an eruv techumin. He was challenged that attending shul should at least be as much a mitzvah as attending a celebration. He responded that it is not because you can pray at home. And you can see this from the fact that the Sages allowed hiring gentile musicians to play at a wedding meal on Shabbos but did not allow that in shul (contrary to the argument of the early Reformers). Maharam Ziskind argues based on this statement of Maharil that going to shul is not a sufficient mitzvah to allow riding a ferry even if you light Shabbos candles on the boat.
III. The Koblenz Ferry
Rav Chaim Yair Bacharach (17th cen., Germany; Chavos Yair, no. 115 [112 in old editions]) was contacted by a rich man who lived just across the Rhine river from Koblenz, Germany, where Rav Bacharach once served as the rabbi. Most of the year, there was a bridge made of large boats across the river. However, for about three months a year, there was ice flowing down the river that threatened the boats. Instead, there were ferries that took people across. Can the rich man hire in advance a ferry to take him across on Shabbos so he can attend shul? Like Maharam Ziskind, Rav Bacharach quotes the Maharil and says that attending shul is not enough of a mitzvah to allow this. Even if this man is the tenth and without him there would be no minyan in town, and even on Rosh Hashanah (if this was an issue), he would not be allowed to take a ferry across the river to attend shul. However, if there are reaction ferries built as flat rafts on top of boats that move almost entirely on their own, Rav Bacharach allows a Jew to go on such a ferry if the Jew enters the boat without saying anything to the ferry driver and only uses on it in order to attend shul (and return). Part of the reason to allow this is that it does not look like any other kind of boat. Apparently, this did not serve the needs of the rich man in Koblenz because he asked the same question to another rabbi of Koblenz, who joined the community a few decades later.
In 1698, a year after beginning to serve as rabbi of Koblenz, Rav Ya’akov Poppers was asked this same question and he sent his proposed responsum to a higher rabbinic authority who replied with his own responsum (Responsa Shav Ya’akov, no. 16). Rav Poppers leans towards permitting usage of the reaction ferry if there are also gentile passengers so that any work would be done even without the Jewish passenger — and even this would be allowed only if the Jew establishes residency on the boat as Shabbos begins. However, his correspondent does not allow even that and therefore Rav Poppers refuses to rule leniently in practice.
Rav Gershon Ashkenazi (17th cen., Germany; Avodas Ha-Gershuni, no. 123) was also asked about using a reaction ferry on Shabbos. He replies that using such a ferry on Shabbos is rabbinically forbidden because it still is boat travel, which is forbidden. Additionally, even though a reaction ferry can travel across the river on its own, in practice the ferry driver uses a paddle-like tool to guide the boat which is forbidden on Shabbos. Rav Ashkenazi only allows a doctor to use a ferry for someone sick, even not life-threatening, because for such a person one may violate a rabbinic prohibition.
However, Rav Nesanel Weil (the Korban Nesanel, 18th cen., Germany; Nesiv Chaim, 248) permits using a reaction ferry if you establish residency on the boat. Rav Weil’s son found this practice in the city Komik near the Moldau (Vltava) river. The father and son exchanged a number of letters on the subject. The father adopts Maharam Ziskind’s and Rav Ya’akov Poppers’ lenient considerations and rules leniently. He also notes that really he is only justifying a practice that exists in many communities.
Rav Chaim Yosef David Azulai (Chida, 18th cen., Israel; Machazik Berakhah 248:3) concludes that the vast majority of authorities rule strictly on this issue despite Rav Weil’s leniency. Similarly, Rav Chaim Mordechai Margoliyos (19th cen., Poland; Sha’arei Teshuvah, Orach Chaim 399:16) concludes that you should refrain from using a reaction ferry whenever there is not a clear mitzvah need.