Red Heifer is much sought after by all who are looking for the Third Temple. The ashes of the Red Heifer will be needed to cleanse the Temple Mount and the Third Temple before the Temple can be used.

Numbers 19:1. And the LORD* spoke to Moses and to Aaron saying, 2. “This is the ordinance of the teaching which the LORD* has commanded saying, Speak to the children of Israel, so they will bring you a red heifer without spot, in which there is no blemish, upon which a yoke has never come, 3. and you will give it to Elazar the priest so he can bring it outside the camp, and one will slay it before his face 4. And Elazar the priest will take of its blood with his finger and sprinkle of its blood directly in front of the Tent of Meeting seven times, 5. and one will burn the heifer in his sight, its skin, its flesh, and its blood, he will burn with its dung. 6. And the priest will take cedar wood, hyssop, and scarlet and cast it into the midst of the burning of the heifer. 7. Then the priest will wash his clothes and he will immerse his flesh in water, and afterward he will come into the camp and the priest will be unclean until the evening. 8. And the one who burns it will wash his clothes in water and immerse his flesh in water, and will be unclean until the evening. 9. And a man who is clean will gather up the ashes of the heifer and lay them up outside the camp in a clean place, and it will be kept for the congregation of the children of Israel for a water of sprinkling: it is an offering of purification. 10. And the one who gathers the ashes of the heifer will wash his clothes and be unclean until the evening, and it will be for the children of Israel and for the stranger that lives among them, for a statute forever.