Esther 7:9 Then Harbona, one of the eunuchs in attendance on the king, said, “Moreover, the gallows that Haman has prepared for Mordecai, whose word saved the king, is standing at Haman’s house, fifty cubits high.”
What is seen here is the fact that there were some eunuchs in the vicinity. Whether or not any of them would have heard what Esther had informed the king of is unknown. However, these men would have served in various capacities throughout the night: preparing the meal, pouring drinks, standing guard, etc.
One of these eunuch’s, Harbona (cf. 1:10), at the very least knew of Haman’s plan to murder Mordecai – Esther’s older cousin and the man who had previously saved the king’s life. The fact that the king was just reminded that morning (6:2-3) and now here of Mordecai’s great act of service would have likely upset the king even further to learn that Haman wished him dead. It seems that he was very quick to offer up this information to the king which could lead to the suspicion that few people actually liked Haman. If this is true, then what is found here is that many people bowed down before Haman out of fear, not loyalty, and fear only works for a time and only as long as the individual is holding the bigger stick.
Also, the reader is given some information that has not yet been seen – Haman had the seventy-five-foot-high gallows built at his house. If this does not reveal a sick and twisted individual, then what will? Haman desired to have Mordecai’s body hung just outside the place he lived so that every day he would see him and revel in his own evil triumphs.