8. “And you write about the Yehudim as is good in your eyes in the name of the king and seal what is written with the ring of the king because what is written in the name of the king and sealed with the ring of the king cannot be returned.”
M’nos HaLevi interprets Achashverosh’s words as explicit permission for Mordechai and Esther to could write whatever they wanted since the leaders would ignore the first decree due to Haman’s being hanged and Mordechai’s being promoted. At the very least, they would be confused and will do nothing – for or against the Jews – hedging their bets.
Interestingly, Ramban, in his Torah commentary (on Bireishis 41:42), uses this verse as proof that the king gifting someone a ring is the same as giving one’s personalized signet, or power of attorney.
2. And the king removed his ring that he took from Haman, and gave it to Mordechai. And Esther placed Mordechai over Haman’s house.
When Achashverosh gave his signet ring to Haman (Esther 3:4), the Midrash (Esther Rabba 7:7) showed parallels in the giving of the ring to the story of Yosef, who also received the signet ring of a gentile monarch, Pharoah. R’ Avigdor Bonchek explains that the central connection is the constant presence of an unexpected turnaround in Jewish history.
The Vilna Gaon adds that by giving his ring, Achashverosh gave to Mordechai the honor with which Haman prided himself on, besides his money.