There used to be, says the Midrash, an impenetrable barrier between heaven and earth.
Prior to the Giving of the Torah at Mount Sinai, the physical world was designated as the human’s domain and the spiritual heavens were designated as the G-dly domain (so to speak).
But with the Giving of the Torah all of that changed. For the first time, the spiritual G-dliness of the heavenly spheres would be permitted to come down and integrate into the physical world, and likewise the physical reality would be enabled to be transformed and elevated upward.
When we use physical resources for the fulfillment of a Mitzvah, we are not only doing the right thing, but we are also generating an incredible transformation that helps to make the world a more g-dly place, one step and one deed at a time.