Astrologers. See on ch. 1:20.
Chaldeans. See on ch. 1:4.
Soothsayers. See on ch. 2:27.
Scarlet. Aramaic ’argewan, better, “purple.” Ancient royal purple was deep purplish red in color, more nearly like crimson. That purple was the royal color of antiquity is attested by documentary evidence from the time of the Persians (Esther 8:15; Xenophon Anabasis i. 5. 8), the Medes (Xenophon Cyropaedia i. 3. 2; ii. 4. 6), and later periods. Daniel attests the existence of this custom for the Neo-Babylonian period, which preceded the Persian.
Chain of gold. The custom of honoring favorite public servants of the crown by the granting of gold chains, decorations, or collars existed in Egypt many centuries earlier (see on Gen. 41:42). The custom was common among ancient nations.
The third ruler. Prior to the time that Belshazzar’s place in the kingdom and his relationship to Nabonidus were fully understood (see Additional Note at the end of this chapter), commentators could only conjecture as to the identity of the second ruler in the kingdom. The existence of such a ruler was implied by the promise to make the reader of the mysterious script on the wall “the third ruler in the kingdom.” The queen mother, Belshazzar’s wife, or a son had all been suggested. It was, of course, thought that Belshazzar himself was the first ruler over the empire. Now that it is known that Belshazzar was only a coruler with his father, and hence the second ruler in the kingdom, it is clear why he could bestow no higher position in the realm than that of “third ruler.”