עַ֣ל מֶ֥ה תֻכּ֛וּ ע֖וֹד תּוֹסִ֣יפוּ סָרָ֑ה כָּל־רֹ֣אשׁ לָחֳלִ֔י וְכָל־לֵבָ֖ב דַּוָּֽי׃
On what part will ye yet be stricken, Seeing ye stray away more and more? The whole head is sick, And the whole heart faint;
Read Kabbalistic (mystical) interpretations of Isaiah 1:5: Zohar and classical Jewish mystical sources, free online.