What does "v'Chitechem" mean?
Rashi #1: It means "the fear of you" 1 (based on a Pasuk in Iyov); it is similar to the previous word, "u'Mora'achem."
Rashi #2: It is an expression of "Chiyus" - life. As long as a person is alive, even a one-day-old baby, one does not need to guard him against mice; but once he dies - even Og Melech ha'Bashan, it becomes necessary to do so.
QUESTIONS ON RASHI
Rashi writes: "Homiletically, 'v'Chitechem' comes from the word 'Chiyus' (life)." But there is no letter Yud in "Chitechem"?
Gur Aryeh: The Torah purposely uses a related spelling to convey an additional meaning; to show that animals' fear of humans is a result of the latter being alive.
Rashi writes: "Your fear is placed upon the animals, as long as you are alive." The Gemara (Shabbos 151b) adds that a lion generally does not attack two people, unless they appear to him to be animals. Why are these facts so?
Maharal (Chidushei Agados Vol. 1, p. 80, to Shabbos 151b): a) Animals are afraid of the Tzelem E-lokim of people, which remains only while the person is alive. b) When a person is alone, he reaches only the initial physical level of Chomer; his Tzelem E-lokim is lacking, and he is vulnerable to attack by animals that possess greater strength in the physical plane. When two people join together, their Tzelem E-lokim is evident, and an animal will not attack. c) If a person conducts himself like an animal, however, he negates his Tzelem E-lokim, and animals can sense this.