THERE IS MORE to the story of the supernatural writing on the wall of the king of Babylon’s palace than you’ve been told.

This week, we begin examining one of the most mysterious and spectacular events of the Old Testament—the message from God to the regent of Babylon, Belshazzar.

According to ancient records, Babylon was captured by Cyrus II, king of the Medes and Persians, in 539 BC on the eve of the 17th of Tashritu on the Babylonian calendar. Belshazzar’s father, King Nabonidus, had ruled Babylon for about seventeen years. Unlike Nebuchadnezzar, who died in 562 BC, Nabonidus was not Chaldean. He was an Assyrian from the northern Mesopotamian city of Harran who’d seized the throne in 556 BC.

More important, Nabonidus was a devotee of the moon-god Sîn. Historical records suggest that he wanted to elevate Sîn to the top spot in the Babylonian pantheon, replacing the chief god Marduk and overturning about 600 years of religious tradition.

The drunken feast held by Belshazzar described in chapter 5 of the Book of Daniel is usually described as evidence of the decadence of Babylon, and that the kingdom’s fall to the Medes and Persians was a just reward for the sinful ways of the Chaldeans. It certainly was that—but it was much more.

The army of Cyrus had defeated Nabonidus at the Battle of Opis, about sixty miles from Babylon, about two weeks before Belshazzar’s feast. The regent must have known that Cyrus was outside the walls of the city. The timing of the feast coincided with an annual festival in honor of the moon-god held in Nabonidus’s home city of Harran, where his mother was a priestess of Sîn. The 17th of Tashritu falls during the Hunter’s Moon or Harvest Moon, two of the brightest full moons of the year.

So, it’s possible that Belshazzar and his nobles weren’t recklessly partying while the Persians were at the gates of Babylon—they may have been trying to summon the protection of the moon-god when he was at full power.

But Belshazzar made a fatal mistake. He “commanded that the vessels of gold and of silver that Nebuchadnezzar his father [meaning his predecessor on the throne of Babylon] had taken out of the temple in Jerusalem be brought, that the king and his lords, his wives, and his concubines might drink from them.” (Dan. 5:2, ESV)

The real significance of the writing on the wall is this: the 17th of Tashritu is 17 Tishri on the Hebrew calendar. That’s second day of the most important feast of Yahweh, Sukkot, or the Feast of Tabernacles. And during this time sacred to God, Belshazzar ordered that vessels sacred to Yahweh be used in a ritual meal for the moon-god, Sîn.

Boom. Babylon fell that very night.