Esther 5:8, 14

If I have found favor in the sight of the king, and if it pleases the king to grant my petition and fulfill my request, then let the king and Haman come to the banquet which I will prepare for them, and tomorrow I will do as the king has said.”

Then his wife Zeresh and all his friends said to him, “Let a gallows be made, fifty cubits high, and in the morning suggest to the king that Mordecai be hanged on it; then go merrily with the king to the banquet.” And the thing pleased Haman; so he had the gallows made.