Him Cyrus, his grandson by his daughter, expelled from the kingdom, having used the arms of the Persians for the purpose; and hence the chief power was transferred to the Persians. The Babylonians also fell under his power and government. It happened at the beginning of his reign that, by the issue of public edicts, he gave permission to the Jews to return into their own country; and he also restored the sacred vessels which Nabuchodonosor had carried away from the temple at Jerusalem.
Accordingly, a few then returned into Judæa; as to the others, we have not been able to discover whether the desire of returning, or the power of doing so, was wanting. There was at that time among the Babylonians a brazen image of Belus, a very ancient king, whom Virgil also has mentioned. This having been deemed sacred by the superstition of the people, Cyrus also had been accustomed to worship, being deceived by the trickery of its priests. They affirmed that the image ate and drank, while they themselves secretly carried off the daily portion which was offered to the idol.
Cyrus, then, being on intimate terms with Daniel, asked him why he did not worship the image, since it was a manifest symbol of the living God, as consuming those things which were offered to it. Daniel, laughing at the mistake of the man, replied that it could not possibly be the case, that that work of brass— mere insensate matter— could use either meat or drink. The king, therefore, ordered the priests to be called (they were about seventy in number); and, bringing terror to bear upon them, he reprovingly asked them who was in the way of consuming what was offered, since Daniel, a man distinguished for his wisdom, maintained that that could not be done by an insensate image.
Then they, trusting in their ready-made trick, ordered the usual offering to be made, and the temple to be sealed up by the king, on the understanding that, unless on the following day the whole offering were found to have been consumed, they should suffer death, while, on the opposite being discovered, the same fate awaited Daniel. Accordingly, the temple was sealed up by the signet of the king; but Daniel had previously, without the knowledge of the priests, covered the floor of it with ashes, so that their footprints might betray the clandestine approaches of those who entered.
The king, then, having entered the temple on the following day, perceived that those things had been taken away, which he had ordered to be served up to the idol. Then Daniel lays open the secret fraud by the betraying footprints, showing that the priests, with their wives and children, had entered the temple by a hole opened from below, and had devoured those things which were served up to the idol. Accordingly, all of them were put to death by the order of the king, while the temple and image were submitted to the power of Daniel, and were destroyed at his command.
Source: Sacred History (New Advent)