The new social media have brought about a return to an ancient phenomenon, public shaming. Tthis gives us a way of understanding the otherwise bewildering phenomenon of tsara’at.
Lashon hara is an expression of evil. An evil eye (ayin hara) looks for something or someone who is above it, and upon finding it, poisons the person’s tranquility and does not allow him to enjoy things he could have enjoyed.
The Sages were eloquent on the subject of lashon hara, the sin they took to be the cause of tsara’at. But there is a meta-halachic principle: “From the negative you can infer the positive”.Therefore there must in principle be a concept of lashon hatov, good speechץ
Sefer Vayikra is full of discussion of korbanot, both public and private. Many explain that the special status of Shabbat Hagadol has to with Bnei Yisrael’s preparations for the Korban Pesach, which they brought in Egypt right before their liberation came to fruition.