Contributed by: R. Ezra Mizrahi
The main job of the Levi'im was to protect the Mishkan. An interesting question arises when we notice the age that the Levi'im are counted from. The Levi'im were counted from one month old!
How can a one-month-old infant "protect" the Mishkan? A month old infant does not have the physical strength to stand let alone protect a holy site- how can this be?
So indeed, the Torah must be speaking of a different type of "protection". The main point here is that the Levi'im did not provide physical protection for the Mishkan, rather they provided a spiritual protection. The Levi'im had a level of holiness and elevated spirituality that protected the holy aura of the Mishkan.
As we know, the Levi'im did not sin the Egel. They saw Hashem clearly at a time when many people of Yisrael had cloudy judgment and faltered.
The holiness of the Levi'im starts to be infused in their children from one month old and on. This is what the Torah meant when it spoke of a month old child serving as a protector.
This is a true mark for our Jewish nation. We are not a nation of physical strength, sheer might, or vast numbers. Our holiness is what keeps us apart from the rest of the world and what protects our traditions and way of life. With Hashem's help we will embrace our religion with a full heart, for only through Yahadut will the Jewish people survive.