What is a mitzvah?

An act of uniting heaven and earth.

But heaven is spiritual and earth is material. To make spirit and matter one is impossible!

A creature of earth cannot make earth heaven. And a heavenly being cannot bring heaven to earth.

But for you, it is not impossible.

This mitzvah that I am commanding you today is not impossible for you. It’s not even distant. It’s very close to you, in your mouth and in your heart to do it. (Deut. 30:11)

It is close to you because the Torah was given to you both written and orally. (Rashi)

Because within you breathes the Creator of both heaven and earth.

So that when you speak the words of His written Torah, you bring heaven down to earth.

And when you explain the words of His oral Torah, you bring earth up to heaven.

Indeed, you accomplish the impossible every day.

Maamar Ki Hamitzvah Hazot 5730.