Mordechai learns that the decree was approved in Heaven due to the Jews' past sins. He pushes Esther to risk her life by appearing unsummoned before the king. Esther agrees, calling for a three-day fast and accepting that her move will permanently sever her relationship with Mordechai and her past life for the sake of her people. https://www.torahrecordings.com/writings-with-rashi/010_esther/004