Tzaraath (Hebrew: צָרַעַת ‎ ṣāraʿaṯ), variously transcribed into English and frequently translated as leprosy (though it is not Hansen's disease, the disease known as "leprosy" in modern times [1]), is a term used in the Bible to describe various ritually impure disfigurative conditions of the human skin, [2] clothing, [3] and houses. [4] .

In the Bible, tzaraat is a skin disease that can take many different forms, and in particularly bad cases can manifest itself on one’s clothing, belongings, and house, in addition to the skin. According to the rabbis, tzaraat is caused by sin. This makes it a disease like no others; part medical condition, part spiritual pathology.

Tzaraat was an affliction of the skin (or clothing or house) discussed extensively in the Bible (notably the Torah portions of Tazria and Metzora) that would cause the sufferer to become impure and be isolated or “quarantined” from the community.

In modern Hebrew, tzahov means yellow, but what does it mean in the Bible? In Priestly law, impurity is stripped of its mythic origins in the demonic realm but still retains its dangerous, physical presence, and must be mitigated by specific acts of ritual cleansing and banishing, depending on the type of impurity.

In Num 12, Miriam, Moshe's own sister, was afflicted with tzara'at. Does anyone remember why Miriam was so afflicted--what was her transgression? Numbers 12:1. Miriam and Aaron began to talk against Moses because of his Cushite wife. for he had married a Cushite. "Has the LORD spoken only through Moses?" they asked.

Tzara'at is a biblical disease that involved discoloration of one's skin, home, or clothing. Once confirmed by a priest's inspection, it renders the subject ritually impure, requiring them to leave the camp for a period, undergo further inspection, and then a purification process.

In the Jewish folklore, the biblical ‘Tzara’at’ is known as a ‘spiritual disease’ – meaning it was caused by spiritual reasons such as ‘evil gossiping’, for example, as happened to Miriam, Moses’ sister (Numbers 12:1-13). In the old Jewish literature there is a saying which explains the Hebrew name of our weekly Torah portion.

In Leviticus 13 and 14, we encounter a strange disease called tzaraat, which can be contracted by human beings, walls, stones, or cloth.

In the Torah, Parashat Tazria describes the biblical affliction known as tzaraat, normally translated as leprosy. (Though the skin disease in the Bible is afflicted by God as a punishment for certain transgressions, and differs from what is considered leprosy today.)

Tzara’at is often translated as leprosy but it was not a physical disease at all (nor do its symptoms resemble true leprosy). The Talmud (Erchin 16a) states that it was an affliction meted out directly from God as a result of sin.