Notes on the Bible, by Albert Barnes, , at sacred-texts.com
None might enter into the king's gate clothed with sackcloth - This law is not elsewhere mentioned; but its principle - that nothing of evil omen is to be obtruded on the monarch - has been recognized throughout the East in all ages.
Esther's maids ... told it her - Esther's nationality and her relationship to Mordecai were probably by this time known to her attendants, though still concealed from the king. See Est 7:4.
The golden scepter - In all the numerous representations of Persian kings at Persepolis the monarch holds a long tapering staff (probably the scepter of Esther) in his right hand. It was death to intrude on the privacy of the Persian king uninvited.
From another place - i. e. "from some other quarter." Mordecai probably concluded from the prophetic Scriptures that God would NOT allow His people to be destroyed before His purposes with respect to them were accomplished, and was therefore satisfied that deliverance would arise from one quarter or another.
Thou and thy father's house shall be destroyed - i. e. "a divine vengeance will overtake thee and thine, if thou neglectest thy plain duty." Though the name of God is not contained in the Book of Esther, there is in this verse a distinct, tacit allusion to God's promises, and to the direction of human events by Divine Providence.
Again the religious element shows itself. Esther's fast could have no object but to obtain God's favor and protection in the dangerous course on which she was about to enter.