Mitzvos are not just something we do. When we perform mitzvos they, in turn, act upon us and change us.
Though we may be unaware of it, mitzvos infuse us with an aura, an energy of sorts called kedushah, as we say twice a day in Krias Shema: ... so that you shall remember and perform all the mitzvos and thereby be holy to your G-d.
It is noteworthy that the same passage first states that we must guard our eyes; the next step is that tzitzis reminds us to perform the mitzvos; and finally, it is then that mitzvos make us kadosh.
Why, though, did the Torah not say right away that performing mitzvos makes us holy? Why bring in guarding one's eyes?
It must be, explains the Chofetz Chaim, that the ability for mitzvos to have their effect is not automatic. Without our having shmiras einayim the mitzvos cannot "work their magic" and infuse us with kedushah.
The Chofetz Chaim elaborates with a mashal:
Picture this: You live in a slum. Not any old slum but one of those most miserable slums in the villages of a third-world country. Your hut has mud floors, chickens scurrying in and out, and the only running water is the water dripping in through a leak in the roof.
Suddenly, rumbling and bouncing down the pitted road is a moving truck. You and your neighbors pop your heads out to see what the commotion is all about, and you see that the truck stops before your home! Wide eyed, you - and your neighbors - watch as movers empty the truck's contents into your home:
In short order, a fine hand-woven carpet, elegant draperies, and a dining- oom set with velvet chairs are all arranged throughout your hut. Apparently you won the Bangladeshi version of a Chinese Auction and since you don't have a phone, they couldn't reach you to share the good news.
But guess what? Your home looks absolutely no better than before. It, in fact, looks ridiculous.
The Chofetz Chaim explains:
"Studying Torah and serving Hashem can change a person and can make him more holy. But when? Only when one does not invite in the yetzer hara's sludge. Fine decorations can upgrade and beautify a decent home, but they are totally worthless in a slum."
Torah and mitzvos can change us. Within them is an incredible amount of kedushah. But if we wish them to reside within us and impact upon our lives, we have to create within ourselves an environment where they wish to remain.
If we do, the mitzvos can truly transform us.