Midrasch zu Tehillim 7:13

“The king said: Who is in the court? Haman had come into the outer court of the king's palace, to tell the king to hang Mordekhai on the gibbet that he had prepared for him” (Esther 6:4).
“To hang Mordekhai on the gibbet that he had prepared for him.” It is taught: He [Haman] prepared it for himself, and about him it is said: “Then against himself he readies deadly weapons, and makes his arrows sharp” (Psalms 7:14), and “He dug a pit and deepened it and he fell into the trap he made” (Psalms 7:16).

“Haman entered, and the king asked him: ‘What is to be done to the man whom the king wishes to honor?’ Haman said in his heart: Whom would the king delight to honor besides myself?” (Esther 6:6).
“Haman entered, and the king asked him… Haman said in his heart.” The wicked are controlled by their hearts: “Esau said in his heart” (Genesis 27:41); “The scoundrel said in his heart” (Psalms 14:1); “Yerovam said in his heart” (I Kings 12:26); “Haman said in his heart.” However, the righteous are in control of their hearts. That is what is written: “Hannah was speaking upon her heart” (I Samuel 1:13); “Daniel set over his heart” (Daniel 1:8); “David said to his heart” (I Samuel 27:1). And they are similar to their Creator: “The Lord said to his heart” (Genesis 8:21).