The purpose of the book of Esther is to explain how the Feast of Purim originated. At this time, Purim becomes one of the annual festivals of the Jewish people. It is the celebration of a time when God delivered his people from an almost certain end.

The story begins with a great banquet (chap. 1). King Ahasuerus throws a feast for all the important people of his kingdom. At the climactic point of the celebration, he calls for his queen, Vashti, so that all his subjects can see her great beauty. She refuses, creating a crisis. After all, this banquet likely had as its purpose the assertion of the king’s authority over his leaders, and this disobedience could not be tolerated. Vashti is deposed, and the search begins for a new queen. The king takes full advantage of this opportunity and tries out many beautiful young women in his kingdom, but none is as outstanding as Esther. Her selection as queen provides background for the action that follows.

In the meantime, Esther’s relative Mordecai also has an experience that carries importance later in the story. Mordecai foils an assassination plot against the king. At this point in the narrative, his action is simply given as information (2:21 23).

The reader is also introduced to one more major character in the book, Haman the Agagite. He is a powerful, evil figure. He hates Mordecai for refusing to show him the respect that he feels is his due (3:1–6). So he determines to kill not just Mordecai but all the Jewish people in the empire. Accordingly, Haman convinces the king to allow him to set a date when all the Jews might be killed. Lots (Heb. purim, from an Akkadian loanword) are cast to choose the date, about a year later (3:7–15).

Mordecai catches wind of the plot and explains the dire situation to Esther. He pleads with her to approach the king to inform him of the plot. Esther hesitates, until Mordecai reminds her that she will not escape the consequences just because she is queen (chap. 4). In the context of this discussion, Mordecai speaks the most famous words of the book when he asks, “Who knows but that you have come to your royal position for such a time as this?” (4:14).

This scene raises the question of who is the hero of the story. Although Mordecai and Esther perform admirable acts, there is a force behind the scenes that the narrative does not name but subtly and certainly makes clear is the hero. It is none other than God himself. The coincidences that follow are just too great to be attributed to chance.

First, Esther is given permission to approach the king, and she successfully invites him to a feast along with Haman (5:1–8). This invitation fuels Haman’s pride. Soon thereafter, the king has difficulty sleeping and asks that the royal annals be read to him. Coincidentally, or so it seems, the part of the annals chosen informs the king of Mordecai’s earlier service in foiling the assassination plot. The king is told that nothing has yet been done to honor Mordecai for his act (6:1–3).

The next morning, Haman comes to court having just constructed a huge gallows on which to execute his enemy Mordecai. When asked by the king what he should do to honor a person whom the king has desired to honor, Haman thinks that it is he who will receive the honor, so he piles up honor after honor. When informed that Mordecai is the one, and that he, Haman, would take a role in honoring him, Haman realizes that his own doom is assured (6:4–14).

Sure enough, at the banquet Esther informs the king of the underside of Haman’s plot. The result is that Haman is killed on the gallows built for Mordecai, yet another ironic reversal in the book (chap. 7).

A problem persists, however. The king has determined a date for the destruction of the Jews, and a decree of a Persian king is irreversible. Although the king cannot reverse his decision to allow the killing of the Jewish people, he can, and does, issue a second decree, permitting the Jewish people to defend themselves (chap. 8). On the fateful day, the Jews are victorious over their enemies, the final and climactic ironic reversal (9:1–19). Purim is established as an annual festival to celebrate this fact (9:20–32).

A deeper significance to this conflict is recovered once it is realized that this is a story of unfinished business. The attentive reader recognizes that Mordecai’s membership in the clan of Kish (2:5) connects him with Saul, since Kish was Saul’s father. On the other hand, Haman is an Agagite (3:1) and therefore related to the Amalekite king Agag, whom Saul, against God’s instructions, did not immediately kill (1 Sam. 15). The story actually begins during the wilderness wandering, when the Amalekites tried to kill off the Israelites before they entered the promised land. At that time, God determined that the Amalekites should be judged and eradicated (Exod. 17:16; Deut. 25:17–19). That a Saulide (Mordecai) defeats an Amalekite (Haman) has deep significance in the past.