The idea of ritual purity may seem strange to us now, but it was central to the sacrificial worship of the ancient Israelites. One could only approach God through sacrifice if one was ritually pure. Ritual impurity had two primary causes: either contact with a corpse ,or anything breaking the skin. In other words, things inside the body had to stay inside the body, or things outside the body had to stay outside the body. So skin disease, tzara’at in Hebrew, was a sign of ritual impurity.
Our rabbis, of blessed memory, believed that disease was caused by sin. They believed that Tzara’at, skin disease, was caused by gossip. They made the connection through a word association. Metzora (one who has skin disease), they argued, was a contraction of the phrase, motzi shem rah, to slander someone, or to gossip.
From this small interpretation, our tradition developed a profound ethic of speech. This tradition reached its apex in the writings of Rabbi Israel Salanter (19th Century LIthuania), who taught that speaking negatively about anyone, when they were not present, was a malignant act that caused spiritual and moral damage to the one who gossiped, the one who heard it, and the one who was the subject.
The idea of ritual purity may be alien to us, and we reject the idea that disease is caused by a moral failing, but the corrosive nature of gossip is something we have all experienced. All of us know the power of gossip to break down the bonds of social solidarity and trust that are the foundation of a healthy relationship. Gossip may not cause skin disease, but it poisons relationships and communities. That is why Judaism teaches us to avoid it at all costs. Purity of speach is a profound Jewish value. It is also a very difficult value to live up to.