It is at the very feast that he has organized where it is clearly shown that Belshazzar does not live in fear of the Lord. It is he who humiliates and mocks the Lord right now, at this feast, by drinking from the cups dedicated to the holy service of the Lord. The partygoers drank from the cups of the Lord while giving praise to idols. They acted as if the Lord did not exist, as if he was nothing. Belshazzar did this while he knew very well the history of his great example Nebuchadnezzar.
Belshazzar’s grievous sin is not just that which happened at the feast. The issue is that throughout his life and government he did not give the Lord the honour that was his due. Belshazzar cannot say, I did not know.
He is without excuse. Someone who knows better is also more responsible.
That is how the Lord God still judges. We also see this later when the Lord Jesus says, And you, Capernaum, will you be exalted to heaven? You will be brought down to Hades. For if the mighty works done in you had been done in Sodom, it would have remained until this day. But I tell you that it will be more tolerable on the day of judgment for the land of Sodom than for you
(Matthew 11:23–24). It is vital to always be examining your life. What is decisive is this: to live with heart and soul to the glory of Christ.
23 but you have lifted up yourself against the Lord of heaven. And the vessels of his house have been brought in before you, and you and your lords, your wives, and your concubines have drunk wine from them. And you have praised the gods of silver and gold, of bronze, iron, wood, and stone, which do not see or hear or know, but the God in whose hand is your breath, and whose are all your ways, you have not honored.