Illustration Credit: Elad Lifshitz, Dov Abramson Studio

After a person’s צָרַעַת (tzara’at) is healed, there is a complicated ritual for purification, involving scarlet wool, cedar wood, and a plant called אֵזֹב (eizov, hyssop—part of what we call za’atar today). All this gets dipped into the blood of a bird.

Midrash Tanhuma explains that a cedar tree is tall, symbolizing arrogance, which can cause a person to sin and get tzara’at. The healing process requires the person to become more humble, which is symbolized by hyssop, a very short plant.

In the Kuzari, Rabbi Yehuda Halevi argues that טֻמְאָה (tum’ah, impurity) is about loss of life, or distance from life. The ingredients for purification from tzara’at symbolize a return to life. The wool is red and so is the cedar wood, and red symbolizes blood, which can represent life. The birds are described as צִפֳּרִים חַיּוֹת (tzipporim hayyot, live birds) and it all goes in מַיִם חַיִּים (mayim hayyim, living waters).