קבלה אויף בראשית 3:15

This is why whosoever does not bow when reciting the blessing of “submission-Modim-מודים,” after seventy years his spine will become a snake.⁸¹Talmud Bavli, Bava Kamma 16a The matter of seventy years is that it refers to the seventy ministering angels who stand in a circle [around the Sefirot] and the snake-Nachash-נחש is positioned to their exterior, standing in ambush around the qualities of victory-Netzach and majesty-Hod.⁸²That is, the qualities of victory-Netzach and majesty-Hod are the two legs and feet, and it states about the snake-Nachash-נחש (Genesis 3:15), “You shall strike at their heel.”