RAV KOOK ON Shemini Part 1: Immersion in Water

f any of these dead [animals] falls on a vessel, it will become unclean.... That article must be immersed in a mikveh ...” (Lev. 11:32) The topic of ritual impurity is a difficult one. This impurity is not a tangible quality that may be seen or felt. It is a spiritual contamination, the result of association with death. To purify ourselves from this contamination, we must immerse ourselves in a natural spring or a ritual bath (mikveh) filled with rainwater.