Ohalos 3:5-6

Ohalos 3:5

According to Rabbi Akiva “mixed blood” means that half a reviis came out before the person died and half after; Rabbi Yishmael says a reviis before he died and a reviis after. Rabbi Elazar bar Yehuda says: both of these are like water (i.e., ritually pure). Rather, mixed blood refers to a crucified person whose blood is gushing and a reviis of blood is found under him; such blood is ritually impure. However, if a corpse’s blood is dripping and a reviis of blood is found under him, that blood is ritually pure. Rabbi Yehuda disagrees, maintaining that the blood that gushes is pure and the blood that drips is impure.

Ohalos 3:6

Regarding an olive-sized piece of a corpse, the minimum size of an opening vis-à-vis impurity is one handbreadth; for a whole corpse, the minimum size is four handbreadths. This protects other (closed) openings from being rendered unclean but an opening of one handbreadth is enough to enable the impurity to pass through to the other side. A piece larger than the volume of an olive is the same as a whole corpse; Rabbi Yosi says that the spine and the skull are like a whole corpse. (Whether Rabbi Yosi’s position is intended to be in addition to or to the exclusion of the opinion that precedes it is a subject of dispute.)