In memory of Rabbi Levi Yitzchok ben R' Zalman Yuda Deitsch OBM
Regarding the days of Moshiach, it is said, "And I will take away the heart of stone out of your flesh" (Ezekiel 36:26)- specifically a heart of stone, and not a brain of stone, for it is very difficult to change the heart of stone before the days of Moshiach. Changing the heart is something that depends upon Moshiach. In contrast, it is possible to prepare the brain even today - through our divine service during the time of the exile. Therefore, we talk about such lofty matters in order to remove (at least) the brain of stone.