A mortal king reaches the ultimate peak of pride, setting the stage for a sharp rebuke that exposes the vast gap between his arrogance and his fragile reality. Belshazzar directly rebels against the Lord of Heaven [מצודת דוד, שטיינזלץ]. The clearest display of this defiance is his decision to bring the sacred vessels from the Temple to his royal feast. He does not do this out of a shortage of drinking cups in the palace. By supplying these holy items to his massive entourage of lords, wives, and concubines, his clear intention is to show disrespect and to purposely anger God [אבן יחיא, אלשיך]. Furthermore, drinking wine from these vessels is not merely a physical act of celebration. It is a calculated ritual of pouring wine as an offering to idols, using the very tools meant for holiness [אלשיך].
This rebellion highlights the deep foolishness of idol worship. Belshazzar chooses to praise gods made of metal, wood, and stone [שטיינזלץ]. These objects are completely without sense and cannot see, hear, or know anything [מצודת דוד, אבן יחיא]. A bitter irony is at play. A person shapes a mute statue with his own hands and then places his total trust in a lifeless lump of material [מלבי״ם]. Belshazzar acts in the exact opposite way of how a person should behave [שטיינזלץ]. He showers praise and glory upon blind and deaf statues, yet he refuses to offer even the most basic level of respect to the true God [אלשיך].
This spiritual blindness is especially shocking because God is the one who actively holds the king's very breath and controls all of his paths. Even if Belshazzar lacks any love for God, a basic instinct of fear for his own survival should be enough to stop his actions. Instead, the evil in his heart blinds him completely to the danger [אלשיך]. As a result, his punishment perfectly mirrors his crime. Because he places his faith in silent, lifeless idols, he will soon lose his own breath. He is destined to fall dead and become like a silent stone, exactly like the statues he so foolishly worships [מלבי״ם].