Esther 3

"When Haman saw that Mordecai would not bow down or show him respect, he was filled with rage. 6 He had learned of Mordecai’s nationality, so he decided it was not enough to lay hands on Mordecai alone. Instead, he looked for a way to destroy all the Jews throughout the entire empire of Xerxes." v. 5-6
Haman enjoyed the power and prestige of his position, and he was enraged when Mordecai did not respond with the expected reverential bow. Haman's anger was not directed just toward Mordecai, but toward what Mordecai stood for - the Jews dedication to God as the only authority worthy of reverence. Haman's attitude was prejudiced: he hated a group of people because of a difference in belief or culture. Prejudice grows out of personal pride - considering oneself better than others. In the end, Haman was punished for his arrogant attitude. God will harshly judge those who are prejudice or whose pride causes them to look down on others.

Taken from the NLT Life Application Study Bible