Furthermore, not only can the ashes act to purify someone from ‘Tumas Mes’ but additionally, they can also act to nullify death in general. This is because like the Tumah of death (Which is the Inyan of the Poroh Adumah) according to the words of Chazal. They say that if not for the golden calf there would be no concept of death amongst the B’nei Yisroel because there would be a freedom from the angel of death (As it was in the Gan Eden before the sin of tree of knowledge) so the golden calf is also the reason for the impurities of death.
This explains the association between the atonement of the golden calf and the purification from the impurities of death which are co-dependent. Because as a result of the atonement for the sin of the golden calf, automatically the impurity of death disappears (As a result of the cause of the impurities disappearing because the whole concept of death becomes annulled).
Our Sages tell us that when the B’nei Yisroel stood at Har Sinai to receive the Torah from HaShem, they were restored to the original perfection in which man was first created. The Torah reinstated the original, unadulterated bond between HaShem and man, so that man was once more granted "freedom from the Angel of Death" (Midrash Rabbah, Shemos 41:9). But this time, too, the state of perfect connection to HaShem was short-lived. Forty days after the people of Israel stood at Sinai, they transgressed the divine decree "You shall have no other gods before Me" by worshipping a calf of gold. The pestilence of death, introduced into the world by Adams sin and banished at Sinai, was reintroduced by the sin of the Golden Calf. This explains the connection between the Poroh Adumah and the Golden Calf expressed in the Midrashic parable: A maids child once dirtied the royal palace. Said the king: "Let his mother come and clean up her childs filth." By the same token, HaShem says: "Let the Heifer atone for the deed of the Calf" (Midrash Tanchuma, Chukas 8).
In our post-Calf world, the imperfection in our relationship with HaShem finds its most noxious expression in the phenomenon of death. Contact with death thus spawns the most severe form of spiritual impurity, which can be mitigated only by the mother of the Golden Calf, the most supra-rational of the Divine decrees – the Poroh Adumah. This was HaShem's reply to Moshe' cry, Master of the universe! This is a purification?! "Moshe," HaShem said, "it is a Chok, a decree that I have decreed." Certain things are so overwhelming to My creations that they can only be overcome by submitting to an absolute command from an absolute authority. I have therefore commanded laws to instruct you what to do when your lives are touched by death. These are supra-rational, even irrational laws, for only such laws can facilitate your recovery. It is only by force of an utterly incomprehensible Divine decree that you can recover from such utter devastation to a living being's self-definition. Ultimately, however, there will come the day that the original bond between man and HaShem will once more be restored. This time, our prophets promise, it will be immune to disruption by sin, since HaShem will "slaughter the inclination for evil" in the heart of man and "remove the spirit of impurity from the earth," with the result that "death shall cease forever."
