Albert Barnes Commentary Esther 4:2

"and he came even before the king`s gate: for none might enter within the king`s gate clothed with sackcloth." — Esther 4:2 (ASV)

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 imposed upon the monarch—has been recognized throughout the East in all ages.