Esther 9:31
establishing these days of Purim at the prescribed time, just as Mordecai the Jew and Queen Esther had established, and just as the Jewish people had established for themselves and for their descendants. The letter included instructions for their fasting and lamentations.
Esther 4:3
In every province where the order of the king and his edict reached, among the Jewish people there was great mourning, fasting, weeping, and lamenting, and many lay down on sackcloth and ashes.
Esther 4:16
"Go and gather all the Jewish people who are in Susa and fast for me. Don't eat or drink for three days, night or day. Both I and my young women will also fast in the same way, and then I'll go in to the king, even though it's against the law. And if I perish, I perish."
Jonah 3:2-9
"Get up and go to Nineveh, that great city, and proclaim to it the message that I tell you."