There is no usage guidance for this tag … yet!

Usage guidance, also known as a tag wiki excerpt, is a short blurb that describes when and why a tag should be used on this site specifically.

The red heifer (Hebrew: פָּרָה אֲדֻמָּה‎; para adumma), a female bovine which has never been pregnant or milked or yoked, also known as the red cow, was a cow brought to the priests as a sacrifice according to the Torah, and its ashes were used for the ritual purification of Tum'at HaMet ("the impurity of the dead"), that is, an Israelite who had come into contact with a corpse.

For more see here.