וְרָאָ֣הוּ הַכֹּהֵן֮ בַּיּ֣וֹם הַשְּׁבִיעִי֒ וְהִנֵּ֤ה הַנֶּ֙גַע֙ עָמַ֣ד בְּעֵינָ֔יו לֹֽא־פָשָׂ֥ה הַנֶּ֖גַע בָּע֑וֹר וְהִסְגִּיר֧וֹ הַכֹּהֵ֛ן שִׁבְעַ֥ת יָמִ֖ים שֵׁנִֽית׃
And the priest shall look on him the seventh day; and, behold, if the plague stay in its appearance, and the plague be not spread in the skin, then the priest shall shut him up seven days more.
Read kabbalistic (mystical) interpretation of Leviticus 13:5: and classical mystical sources.