Shabbat 122 – For His Own Use – Others Benefit

The Mishnah states that if a non-Jew lights a lamp or lantern on Shabbat for his or her own use, an Israelite can make use of it. But not if the non-Jew lights it exclusively for the Israelite. Similarly an Israelite can make use of a ship’s gangway built on Shabbat, so long as the non-Jew didn’t build it exclusively for the Israelite.

Why is this permissible? Because “a lamp for one is a lamp for a hundred” – that is, nothing is diminished by the Israelite’s use of a lamp already lit.

The rabbis investigate this concept further:

Come and hear: If a city inhabited by Israelites and Gentiles contains baths where there is bathing on the Sabbath, if the majority are Gentiles, [an Israelite] may bathe there immediately;

if the majority are Israelites, one must wait until [after the Sabbath when] hot water could be heated

Water heated for the benefit of a Gentile majority may be enjoyed by Israelites. But not if it is heated for the sake of the Israelites.