: It details the 11 ingredients of the incense and the specific ritual for grinding them.

Your keyword’s four components now cohere:

Because a Kohen (priest) is strictly forbidden from contracting corpse impurity, knowing whether a non-Jewish grave imparts impurity via an ohel is of critical practical importance.

Keritot has only 6 chapters in most editions, so “Keritot 6b page 78” doesn’t align with the usual pagination. Similarly, “Jebhammoth 61” seems like a possible misspelling of Yevamot (tractate on levirate marriage), but Yevamot 61a–b discusses exemptions from levirate marriage, not a “work” in the sense you likely mean.