639. The Difference Between Primary Labors and Subordinate Labors

Shabbos 7:6

Separating milk is considered a subordinate labor of separating because one separates the curds from the whey. If one made cheese on Shabbos, he is performing a subordinate labor of building; any activity that involves gathering separate items and joining them together into a single mass resembles the labor of building. In this manner, each of the primary categories of labor has subordinate labors that are determined based on these principles. Based on the nature of an activity, we can determine in which category of labor it falls or in which category it is a subordinate labor.

Shabbos 7:7

If a person intentionally performs an activity from one of the primary categories of labor or one of the subordinate labors, he is liable for the penalty of spiritual excision (kareis). If there are witnesses, he is liable to execution by stoning. If one performs such an activity without intending to violate the law, he must bring a sin offering. The only difference between primary labors and subordinate labors involves the sacrifices. If a person without intending to break the law performs many activities, each of which is in a different primary category of labor, in one state of unawareness, he must bring a sin offering for each category of labor that he violated. If one performs an activity that violates a primary category of labor and its subordinate labors in one state of unawareness, he need only bring one sin offering.