Jamieson, Fausset and Brown on Esther 9:2

2. The Jews gathered themselves ... no man could withstand them--The tables were now turned in their favor; and though their enemies made their long meditated attack, the Jews were not only at liberty to act on the defensive, but through the powerful influence enlisted on their side at court together with the blessing of God, they were everywhere victorious.

the fear of them fell upon all people--This impression arose not alone from the consciousness of the all-powerful vizier being their countryman, but from the hand of God appearing so visibly interposed to effect their strange and unexpected deliverance.