4. Aveira. Chazal inform us that eating bugs causes spiritual harm [“טמטום הלב”], as the posuk says (ויקרא י''א, מ''ג ), “אל תשקצו את נפשותיכם בכל השרץ השורץ על הארץ, ולא תטמאו בהם ונטמתם בם ... והתקדישתם והייתם קדושים.” It was taught in the beis medrash of R’ Yishmael that an aveira causes spiritual blockage of the heart, reading the word “ונטמאתם” as “ונטמטם” (גמ' יומא ל''ט ע''א ). It similarly causes blockage of the intellect and increases foolishness (פסיקתא סוף פ' שמיני ).
5. Forbidden foods. The food a person eats becomes part of his body and has an effect on his soul. Thus, Hashem forbade us from eating foods that harm our bodies, hearts, and souls (חינוך מצוה קמ''ז ). These foods are like harmful poison to a person (מסילת ישרים פי''א ). One must obviously stay far away from them, just as one would do for a deadly toxin.
6. Dullness. They also defile the pure soul, drive away the spirit of kedusha and tahara from a person, and produce dullness of the intellect and cruel traits (כלי יקר ויקרא י''א א'). Because people are not careful about these matters, children get caught up in bad things and stray. Many people in the generation have chutzpa, and yiras Hashem does not touch their hearts. Even if they would be rebuked to their faces, they do not accept the mussar (פרי חדש יו''ד סי' פ''א סקכ''ו ).
