‘Belshazzar, while he tasted the wine, commanded to bring the gold and silver vessels which Nebuchadnezzar his father had taken out of the temple which was in Jerusalem, that the king and his lords, his wives and his concubines, might drink from them.'
We are not told of any reason why he did this, but he seemingly knew of them and no doubt persuaded himself in his drunken stupor that it was time they were used. It was probably his means of declaring the power of Babylon, and possibly his own defiance of a God Who had helped his grandfather, and Whom he felt had let him down, at a time when that power was being fatally undermined. The fact that they were sacred vessels suggests that this was a direct act of blasphemy, for such sacred things were generally treated with respect. It is clear that Daniel no longer held such high office under Nabonidus and Belshazzar, for he was not called to the feast and is later mentioned as though he was in retirement. It would not be unusual, given the changes in rulership that had taken place. Perhaps also he had previously in times past used his influence against their use.
‘While he tasted the wine' probably means while Belshazzar was under its influence.
The presence of the important womenfolk, including Belshazzar's wives, is attested elsewhere with regard to Babylonian drinking feasts, even though they were feasts of great lasciviousness. Their presence, and the general behaviour at the feast, added to the blasphemy of using the sacred vessels. The concubines would be lesser wives of the harem who were of common stock.
‘Nebuchadnezzar his father' simply means that Nebuchadnezzar was his ancestor. He was in fact his grandfather. The word translated does not strictly mean ‘father'. It means ‘one through whom you trace your descent'. Compare ‘your father Abraham' (Genesis 28:13; Genesis 32:9). (It can also be used in other ways more loosely. Compare the words of Jesus, ‘you are of your father the Devil' - John 8:44).