He deftly gave the clear Thomist answers but then took it a step further. He said that the soul (or spirit) is the differentiator that gives humans reason and free will. Two of the faculties of the soul are the intellect (mind) and the will (often synonymous with the heart).
(Here is the archive link.)
Here's where he develops it further. Religions usually contain some form of sacrifice. As we look at religion with all its varied acts of sacrifice, the highest sacrifice is the Sacrifice of the Mass.
As Catholics we employ sacrifice all the time. Fasting is the sacrifice of the body desire to eat. Celibacy is the sacrifice of the sexual urge. These sacrifices exercise our self-control.
How does this relate to the Will and the Intellect?
The sacrifice of the Intellect is Faith. The Intellect is the striving to know. To discover and to contain all it can find. It is a temptation of the Intellect to believe ONLY what it can apprehend (through the senses). Conversely, the logical fallacy is that if it is not sensible, then it does not exist. Faith then, is letting go of knowing only what I can perceive. It is the accepting of knowledge GIVEN to me rather than acquired by me. It is other-centered and trust-based.
The sacrifice of the Will is Obedience. The Will is the choice maker, the part of me that decides whether to do this or that. The temptation of the Will is to be the captain of my own destiny. To decide that MY wishes are the ends towards which the whole world ought to work. Obedience then, is the letting go of my wants and desires. To act as if another's wishes are actually mine. To make their goals, my goals and their tasks, mine. Again, it is other-centered and trust-based.
What I see from this wonderful insight is that the act of sacrificing something is an indicator of the intrinsic value of the thing sacrificed. Food, sex, knowledge and choice, are all powerful and GOOD. Practicing the sacrifice of them makes us better, and orients us toward the ultimate Good, God.