As we learned above (daf, or page 15) the term kutim refers to those people who were brought to Israel in a population exchange during first Temple times, when the kings of Assyria exiled the Northern kingdom and replaced them with other nations – not all of whom were truly kutim. They settled in the area around the city of Shomron (Samaria), which is why they are also called Shomronim or Samaritans.
In II Melakhim, or Kings (chapter 17) the navi describes how these nations accepted upon themselves some of the Jewish laws and customs out of fear after they were attacked and killed by lions – which is why they are often called gere arayot – converts because of lions. At the same time they did not renounce their own gods and religious traditions. Furthermore, they have their own version of the Torah, which they believe and present as the true Torah. This creates a situation where the kutim are meticulously careful with those mitzvot that are found in their Torah, but will not accept other commandments that they do not find written there.
This becomes important when the Gemara explains the difference in attitude that we have towards a kuti and a non-Jew with regard to renting or leasing to them workplaces that others will perceive as belonging to the Jewish owner. Thus, Rabban Shimon ben Gamliel teaches that a bathhouse cannot be rented to a non-Jew, since he will operate it on Shabbat. The Gemara discusses whether it can be rented to a kuti, since he will not work on Shabbat, although he will heat the water on hol ha-mo’ed – the intermediate days of the festivals – when work unrelated to the festival should be avoided. Once the Gemara concludes that even Jews are permitted to operate a bathhouse on hol ha-mo’ed it becomes obvious that it can be rented to a kuti. On the other hand, Rabbi Shimon ben Elazar teaches that a field cannot be leased to a kuti, since he will work the field on hol ha-mo’ed. Interestingly, the Gemara concludes that Rabbi Shimon ben Elazar would permit renting the field to a non-Jew, since the Jewish owner can insist that the field not be worked on hol ha-mo’edand the non-Jew will listen to him. The kuti, however, cannot be trusted to accept such a limitation, since he is convinced that his understanding of the Torah is better than the Jew’s.