Shabbos 6:10-7:1

Shabbos 6:10

According to Rabbi Meir, a person may go out on Shabbos with a locust egg, a fox tooth or a nail from the gallows when these things are used as part of a cure. The Sages, however, do not even permit one to use these things on weekdays because they are non-Jewish practices.

Shabbos 7:1

An important principle of Shabbos is that if one is unaware about the concept of Shabbos and he performs many acts of labor on many Shabboses, he only has to bring one sin offering. If he knows about Shabbos and he performs many acts of labor on many Shabboses (unaware that it happens to be Shabbos), he must bring a sin offering for each Shabbos he violated. If he knows that it is Shabbos and he performs many acts of labor on many Shabboses, he must bring a sin offering for each category of labor he violated; if he performed many acts of labor within the same category, he only has to bring one sin offering.