Tanya Chapter 37 part 8

Torah study is called “calling through the Torah.”  To study Torah is to call G-d by His Name, turning to His very essence, asking Him to stay with us and not to leave us alone. This deep call from our inner space pulls down the very essence of Hashem over the source of our souls. Being cognizant that we draw down Hashem's essence when we study Torah allows us to experience great awe when doing so.