Esther 2:21
“In those days, while Mordecai sat in the king’s gate, two of the king’s chamberlains, Bigthan and Teresh, of those which kept the door, were wroth, and sought to lay hand on the king Ahasuerus.”
KJV
Read in Esther 2Meaning
The threat shows that even the apparently secure royal court is vulnerable from within. Mordecai's position at the gate places him where he can learn of the conspiracy.