After the Nes of Purim, Esther wanted the story to be written and
recorded in Jewish history. The Chachomim were not happy about the
idea. There is a machlokes Tana'im if the torah alludes to a Megila
written about Esther or not.
Most Tana'im agree that Esther was written with Ruach HaKodesh. The Braisa brings 4 opinions of Tana'im as to the source for this. The gemara brings an additional 3 amora'im that bring their own source. Rava disproves all the sources of the Tana'im and says that the source brought by Shmuel the Amora is the only unquestionable source.
1. "Vayomer Haman B'libo" - Haman says to himself that the king surely wants o honor him (6:6). How does the writer of the Megila know what Haman thought? - Rebbi Eliezer - (Rava asks,maybe this was obviously what he was thinking)
2. Esther found favor in everybody's eyes (2:15). - Rebbi Akiva - (Rava asks, everyone claimed Esther was from their country so obviously they liked her)
3. Mordechai was informed of Bigson and Seresh's plot (2:22). - Rebbi Meir - (Rava asks, Mordechai spoke all the languages nad overheard them plotting)
4. The Yehudim did not take any spoils of the war (9:10). - Rebbi Yosi Ben Durmaskis - (Rava asks, maybe Mordechai and Esther sent out meseengers to tell the Yehudim not to take anything)
5. Kimu V'Kiblu (9:27) Kimu L'Ma'ala Ma SheKiblu L'Mata - The heavens accepted the Yom Tov of Purim - Shmuel - (Rava says this proof is unquestionable)
6. ViMei Purim HaEileh Lo Yaavru Mitoch HaYehudim, the days of Purim will not pass from the Yehudim (9:28) - Rav Yosef -
7. V'Zicrom Lo Yasuf MiZaram, the memory will never fade away (9:28) - Rav Nachman bar Yitzchok