לְהוֹרֹ֕ת בְּי֥וֹם הַטָּמֵ֖א וּבְי֣וֹם הַטָּהֹ֑ר זֹ֥את תּוֹרַ֖ת הַצָּרָֽעַת׃ (ס)
to teach when it is unclean, and when it is clean; this is the law of leprosy.
Read kabbalistic (mystical) interpretation of Leviticus 14:57: and classical mystical sources.