The Temple: Learning the Laws of Taharah and Tumah:
What is the purpose of studying the laws of ritual purity (TAHARAH), such as the laws about the "red cow" (PARAH ADUMAH; Num. Ch. 19)? Do these laws have any relevance nowadays?
These laws have no practical relevance for ordinary Jews (other than Kohanim) when there is no Temple. Except for Maimonides' Mishneh Torah, the standard Jewish law codes omit these topics because they are inapplicable nowadays.
When the Messiah comes, these laws will become relevant again because we will have a Temple again. Even nowadays, studying these laws qualifies as "theoretical" Torah study. Also, even though they don't apply to us today in a practical sense, studying them teaches us about the practices of our ancestors (and our descendants, some day). We can also learn many moral lessons from these laws. For example, the Midrash tells us that the priest's preparation of the ashes of a red cow for purification was an atonement for Aaron's making the golden calf at Mount Sinai. The ashes were mixed with "living water", cedar, and hyssop; this is symbolic of the fact that a person who wants to be cleansed of his sins must become as humble as dust and ashes, must absorb the living water of the Torah, and must be firm as a cedar tree (in rejecting sin) and pliant as a hyssop twig (in reforming).
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