תֶּחְשַׁ֣כְנָה עֵ֭ינֵיהֶם מֵרְא֑וֹת וּ֝מָתְנֵ֗יהֶם תָּמִ֥יד הַמְעַֽד׃
Let their eyes be darkened, that they see not; And make their loins continually to totter.
Read kabbalistic (mystical) interpretation of Psalms 69:24: and classical mystical sources.