Shema-Shabbat HaGadol-Hidden Changes Within
It is written in the Haftarah for Shabbat HaGadol, “I am God, I do not change (Malachi 3:6).” With regard to the wicked, however, God does change, but He conceals Himself with many covers. Such individuals are empty and desolate. With respect to such people, it is written, “I will hide My face from them (Deuteronomy 32:20).”
When a person fears God and is aware of His presence, then God never changes. Any changes merely involve the many garments and concealment with which God covers Himself.
I heard from my master, the Baal Shem Tov, that if a person realizes that God is hidden, He is really not hidden. It is thus written, “All the workers of iniquity shall crumble (Psalms 92:10),” for all barriers of evil crumble before such an individual.
It is therefore written, “I will hide My face (Deuteronomy 31:18).” That is, God will be hidden so that they do not even know that He is there.
The important rule is that nothing can separate a person from God when he prays and studies Torah, even if he has many ulterior thoughts. When an individual is aware of this, he will realize that God is hidden even in these thoughts. When a person knows that God is hidden, He is not really hidden. (Toledot Yaakov Yosef, Beraishit)
When we ask that God “Illuminate our hearts,” we are asking Him for the clarity that comes with Torah study and Awe of Him, that allows us to see that He is not Hidden.
This can also be added as a Kavanah in Morning Blessings: Who opens the eyes of the blind.”