According to the law - An exception to the ordinary practice of compulsory drinking had been made on this occasion by the king’s order.

Law. —Rather ordinance or decree, that is, specially issued for this occasion. What this means is shown by what …

And the drinking was according to the law, none did compel ,
&c.] According to the law Ahasuerus gave to his officer…

As pride rose in Ahasuerus's heart with the grandeur of his kingdom, he made an extravagant feast. This was vainglory. A dinner of herbs with quiet…