The Divine command to take a red cow which is unblemished, burn it, mix its ashes with water, and sprinkle it on one who is tameh meis (spiritually contaminated because of contact with a dead body) defies explanation. Indeed, this is why it has been classified as a “chok,” a mitzvah whose underlying rationale is inaccessible to human comprehension. Nonetheless, a variety of commentators provide us with insight into this mitzvah.
Horav S.R. Hirsch z.l. opines that issues which deal with contamination and purification, ideas associated with the spiritual realm, are inherently difficult for the human intellect to grasp. In discussing some aspects of the halachos of parah-adumah he offers an explication of the conceptual foundation. The two colors which represent the entire spectre of human abilities and endeavor are red and white. Red is associated with the physical dimension, the animal drive which is devoted to the will to live. White, on the other hand, symbolizes purity and the Divine. The physical dimension, lacking the spiritual element, is perishable. Hence, red represents impermanence and transience. White, the perfect color, encompassing all the colors in complete harmony, is the symbol of the eternal.
When man confronts human mortality, he experiences a spiritual risk. At that moment, the reality of his physical limitations envelopes him. Specifically at this time, the individual encounters death. The power of nature is represented by the color red. The kohen, dressed in white, comes forth to reduce the red cow to ashes. This act confirms that the spiritual always prevails over the physical and that the spiritual never abnegates its essence in the face of death.
This is the only time that the ashes of an animal are mixed with water and ritually sprinkled. All other “sprinklings” are performed using the blood of the sacrificial animal. Horav Hirsch suggests that these ashes represent the ultimate end of the animal, formerly resplendent with vigor and vitality. This symbol emphasizes for us the frailty and impermanence of all material existence, while coincidentally bringing to mind the eternal character of the spiritual dimension.
The ashes of the parah-adumah, which when sprinkled transform the impure to pure, simultaneously transforms the pure kohen into an impure state. This paradox symbolizes the essence of the human condition. Man is able to confront and conquer the challenges of his flesh/physical dimension, as long as he draws strength from the spiritual realm. Although the spiritual dimension becomes momentarily diminished through its contact with the physical, it ultimately rejuvenates when it differentiates from the physical to assume its original design. Likewise the kohen who becomes impure eventually becomes pure again.