Water of lustration

The water of lustration or water of purification was the water created with the ashes of the red heifer, according to the instructions given by God to Moses and Aaron in the Book of Numbers.

The Hebrew Bible taught that any Israelite who touched a corpse, a Tumat HaMet (literally, "impurity of the dead"), was ritually unclean. The water was to be sprinkled on a person who had touched a corpse, on the third and seventh days after doing so, in order to make the person ritually clean again. A tent in which someone had died was similarly considered to be unclean.

The water was to be used as follows:

The water was used again in Numbers 31:23 for the purification on the metallic booty brought back by the Israelites following their victory over the Midianites.

In other biblical translations the water is referred to as water of expiation (Douay-Rheims Bible), water of separation (King James Version), water of cleansing (New International Version) or water for impurity (American Standard Version). The Jerusalem Bible uses the term lustral water. In Hebrew, the water was called mei niddah by the Torah and mei chatat by Chazal.

John Wesley stated that the term 'water of separation' indicated that the water was 'appointed for the cleansing of them that are in a state of separation, who for their uncleanness are separated from the congregation'.Thomas Coke noted that 'the heathens had their water of lustration with which to sprinkle themselves in token of purification', and thought this was probably borrowed from the Mosaic law.Albert Barnes used both terms: 'the water of purification' to describe the purifying effect of the water, and 'the water of separation' to refer to the state of legal separation from the community, for which the water was to act as a remedy.

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