How Is Tumas-Mes Conveyed?
1. A kohen may not touch any part of a dead person.
2. He may also not touch any person or utensil that is at this moment connected to a corpse through touching, carrying, or being under the same roof.
3. A kohen may touch a utensil that is touching someone or something that is in contact with a corpse. But he may not touch a person who is touching something that forms a roof (ohel). Nor may the kohen touch a person who is under the same roof as the corpse, or a person who has part of his body directly above or directly below the corpse. Because of this rule, when people are crowded tightly together and one of them is under the same roof as a corpse (or one of his limbs is above or below the corpse), a kohen may not touch anyone in the crowd.
4. A kohen may not carry or move a corpse or part of a corpse. It is forbidden to do so even indirectly. For example, if a corpse is lying in a small boat, it is forbidden for a kohen to step into the boat if this makes the boat (and corpse) move.
5. Tumas-mes spreads directly above and below any part of a corpse or a grave. Therefore, a kohen may not bend his body or even put his little finger over a corpse.
6. Furthermore, tumas-mes spreads under the entire roof, cover, or overhang that is sheltering a corpse. Therefore, if a corpse is under a balcony or a wide branch, a kohen is forbidden to stand underneath that balcony or branch.
When Does the Rule of Ohel Apply?
7. Tuma spreads under a roof only when the roof is sheltering at least a cubic tefach of space.
8. Movable articles left temporarily under the roof are not considered to be taking up the space of the cubic tefach.
9. Tuma spreads from one roof to the next roof even if the two roofs are different heights, so long as there is no space between them and each roof shelters a cubic tefach of space.
10. If a roof narrows until it is less than a tefach, tuma still spreads under the narrow part of the roof (so long as the majority of the roof is a tefach wide) since it is all one roof. Therefore, if a corpse lies under a beam a tefach wide at both ends, but narrower than a tefach at some point in the middle, a kohen may not go under any part of the beam.
11. Some authorities contend that the small branches and leaves of a tree with dense foliage combine to create a roof, even though each branch or leaf is not a tefach wide. This applies only if the leaves and branches are so close to one another that they could be glued together with clay into one surface.
12. A moving roof does not convey tuma. Therefore, if an airplane flies directly over a corpse, the tumas-mes will not spread under the whole airplane the moment it passes over. (Everything inside the plane, however, will become tamei.) Also, if ice or snow cover the space between the two roofs, the roofs are not considered joined, and tuma will not spread from one roof to the next.
Partitions and Openings
13. A partition ten tefachim high does not prevent tumas-mes from spreading under a roof, and even a hole in a wall can be enough to allow tuma to spread from one room to the next.
14. The size of this hole depends on its purpose. If it was made to pass items through or to see through, it must be a square tefach for tuma to pass through. If the opening is less than a tefach in either height or in width, tuma will not pass through.
15. If the opening is for light, tuma will sometimes pass through, even if the opening is smaller than a square tefach.
16. A breach made in a wall unintentionally must be at least the size of an average person’s head for it to convey tuma.
17. How can such openings be sealed?
- If an object not susceptible to tuma fills the entire hole, it is considered blocked, even if one intends to remove it later on.
- If the object placed in the hole does not block it completely, but only reduces it to less than the regulation size, the object must be left there indefinitely.
- An object that is susceptible to tuma cannot be used to block such openings unless it is fixed in place permanently and becomes part of the building.