Parah 8:1-2

Parah 8:1

Let’s say that two men were guarding the trough of water for sanctification. If one of them was rendered ritually unclean, the water remains valid because it’s still being supervised by the other person. If the first person was purified and the second person was rendered unclean, the water remains valid because it is now being supervised by the first person. If both of them were rendered unclean simultaneously, the water is invalidated. If one of them performed some unrelated task, the water is valid because it remains under the supervision of the other. If the first stopped doing the task and then the second performed some task, the water remains valid because it’s now being supervised by the first person. If both performed unrelated tasks simultaneously, the water is invalidated.

Parah 8:2

The one who mixes the sanctification water may not wear his sandals because if some liquid falls on a sandal, it’s rendered ritually unclean and conveys impurity to the wearer. We observe that liquids don’t render a person impure but they render a sandal impure, which then renders the person impure. If some liquid falls on a person’s skin, he remains clean; if it falls on one of his garments, the garment is rendered unclean and conveys impurity to him. We observe that liquids don’t render a person impure but they render clothing impure, which then renders the person impure.