Charles Ellicott Commentary Esther 1:13

"Then the king said to the wise men, who knew the times, (for so was the king`s manner toward all that knew law and judgment;" — Esther 1:13 (ASV)

Which knew the times. —That is, who were skilled in precedents, and could advise accordingly.

For so... —Translate, for so was the king’s business laid, before ...