Then his wife Zeresh and all his friends said to him, “Let a gallows fifty cubits high be made, and in the morning tell the king to have Mordecai hanged upon it. Then go joyfully with the king to the feast.” This idea pleased Haman, and he had the gallows made.
This account here given of Haman is a comment upon that of Solomon, Pro 21:24. Proud and haughty scorner is his name that deals in proud wrath. Never did any man more answer that name than Haman, in whom pride and wrath had so much the ascendant. See him, I. Puffed up with the honour of being invited to Esther's feast.
Commenting on Esther 5:9-14
Then said Zeresh his wife and all his friends unto him, Let a gallows be made of fifty cubits high, and to morrow speak thou unto the king that Mordecai may be hanged thereon: then go thou in merrily with the king unto the banquet. And the thing pleased Haman; and he caused the gallows to be made. (g) Meaning, the highest that could be found.
Let a gallows be made of fifty cubits high - The word עץ ets, which we translate gallows, signifies simply wood, a tree, or pole; and this was to be seventy-five feet high, that he might suffer the greater ignominy, and be a more public spectacle. I believe impaling is here also meant. See the note, Est 2:23 (note).