The Chofetz Chaim applies this posuk as a lesson of the respect and reverence to be given to a Torah scholar. The Jewish people were instructed not to touch Har Sinai, due to its consecration as the place where the Torah would be given. This honor was extended to a harain, although it has no mind or feelings; how much more so should one be careful of in the respect afforded to a Torah scholar, one who has actually studied and absorbed the Torah.
The Ateres Mordechai suggests a more homiletic approach. Often ulterior motives and personal interests can cloud a situation so, that which is crooked will appear to be straight, and that which is clearly improper suddenly becomes appropriate. The Bnei Yisroel as they are about to receive the Torah are admonished not to allow these personal subconscious concerns to distort the true essence of the Torah. Kol Hanoge Bahar do not allow your personal Negius (interests, motives) to interpret the Torah to suit yourself. Do not justify your lifestyle with misguided explanations and definitions. The Torah must always remain the paragon of perfection as it was given on Har Sinai.
