וחי בהם
If one cannot/does not live bahem, in them (Torah and mitzvos), he has no life; he is not living in the true sense of the word. A life without purpose is not living. Torah gives purpose to life. The Chiddushei HaRim interprets the enjoinment of V’chai bahem as an exhortation to live through mitzvah performance; mitzvos should be alive, our primary sense of joy, through which we enthusiastically live life to the fullest by observing mitzvos to perfection. Anyone who has ever davened well, studied through a difficult blatt, page, of Gemorah will attest to such an ecstatic, rapt feeling….