The four deaths mentioned in the Jewish law have a very straightforward physical impact on the body. All of them cause inability to breathe which is linked to "maintenance" of the soul, and thus cause death:
- Crushing the chest and the lungs by stoning
- Burning the throat and the trachea
I find it difficult, however, to explain a death caused by a drop of poison - there's no physical damage is caused to the body and no disruption to breathing.
How do our sources explain the mechanism of death by poisoning?