Hashem commands the Jewish people to be holy. "You shall be holy unto Me because I am holy." [i]
Why does G-d being holy require us to be holy? And what does it even mean to be holy? What is holy? I can understand that Hashem is holy, even if I do not understand what holiness is, but how does a simple Jew become holy?
The answers to all these questions are easier than they seem; if you understand the words we say many times a day in the blessings, "…Asher kidishanu b'mitzvotav…."
It is surprising how few people understand even the simple translation of these words, let alone what they actually teach. At best most say that they mean, "Who has sanctified us with His commandments." But what does "sanctified" mean? There is a common misunderstanding that "sanctified" means "separated". It does not mean to separate. One of the results of sanctification is "separation" but sanctify does not mean to separate.
When we shower before going into the mikvah we separate ourselves from the dirt that was on our bodies. When we go into the mikvah we receive the purity that the mikvah bestows. The mikvah does not separate us. It purifies us.
So do all mitzvahs purify us. The root of sanctified (kidishanu) is "holy". The blessing tells us that when we fulfill a commandment we become holy.
What this tells us is that when doing a mitzvah we should feel tremendous appreciation. The mitzvahs are deeds designed to make us holy. What could possibly bring us more joy than that? If indeed we are serving Hashem, and He in His kindness gave us these tools to accomplish His desire, what could possibly give us more joy than fulfilling His wish for us?
But still, what is holy? What is holiness?
The fact is that only Hashem is holy, and everything that we call holy, be it a sefer Torah, tefillin, a righteous person…, all these merely point to Hashem. And all that we call unholy, points us away from Hashem!
But wait a minute! Hashem is infinite. The Infinite is everywhere. How can anything point to or away from the Infinite?
Holiness helps to reveal G-d's Presence in this lower world. But man cannot see G-d and live. So what does it mean to reveal G-d's Presence? It means that G-d, in His kindness, thins out the thick clouds of coverings and He shows us that He is in fact present. G-d is always present, but in order to give us freewill He has to hide. Fulfilling mitzvahs with joy helps to remove the husks that hide Him from us.
Whether you call our service working to reveal His Presence (gilui ha-Shechina), or making a dwelling place for Hashem in this lower world (dirah tachton), our job as Jews is to elevate the physical world by using it for holiness, and in the end we will see that Hashem always filled and surrounded all.
What does Hashem's holiness have to do with us striving to become holy? Hashem wants us to experience His holiness, and in order to do this we ourselves must become holy. "Holy, Holy, Holy, is the L-rd of Hosts the whole world is filled with His glory."[ii]