Chasing physical pleasures creates a thick wall around the human spirit, whereas pursuing spiritual wisdom breaks down those barriers and refines the soul. A deep divide exists between those who drown themselves in physical desires and those who find their ultimate joy in serving God.
The hearts of those who chase after worldly pleasures become numb and completely blocked, as though they are covered and clogged by a thick, heavy layer of fat [מאירי, ביאור שטיינזלץ]. This concept of a fattened heart is the very root of foolishness, as the heavy burden of materialism prevents the mind from truly understanding [מצודת ציון]. Drowning in the pleasures of this world and the desire for food breeds this exact foolishness, ultimately leading people to cast off the responsibility of the Commandments [מצודת דוד, מלבי״ם]. Consequently, their hearts become entirely sealed off from serving God. They lose the ability to understand spiritual teachings. Even if they could comprehend the concepts, they would find absolutely no flavor or joy in them because they have completely severed their connection to holiness [רד״ק, אלשיך, מאירי].
In sharp contrast stands the person who actively delights in God's teachings. This joy is a deeply personal, inner pleasure [מאירי, אבן עזרא]. At the same time, it can be seen as a reciprocal relationship, where a person actually brings joy to the Torah itself simply by engaging with it [ביאור שטיינזלץ].
The divide between these two ways of living is absolute. Sinking into materialism closes off the heart, while studying God's teachings opens the mind to true understanding [רד״ק, ביאור שטיינזלץ]. Furthermore, while the hearts of those chasing physical desires grow heavy and coarse, immersing oneself in spiritual study actively weakens physical cravings and drains the power of negative urges [מצודת דוד, מלבי״ם]. By connecting to the holy root of the soul, engaging with God's teachings becomes the truest source of delight, standing in total opposition to the passing, empty pleasures of the physical world [אלשיך].