הַמְעַט־לָ֙נוּ֙ אֶת־עֲוֺ֣ן פְּע֔וֹר אֲשֶׁ֤ר לֹֽא־הִטַּהַ֙רְנוּ֙ מִמֶּ֔נּוּ עַ֖ד הַיּ֣וֹם הַזֶּ֑ה וַיְהִ֥י הַנֶּ֖גֶף בַּעֲדַ֥ת יְהוָֽה׃
Is the iniquity of Peor too little for us, from which we have not cleansed ourselves unto this day, although there came a plague upon the congregation of the LORD,
Read kabbalistic (mystical) interpretation of Joshua 22:17: and classical mystical sources.