You ask: Why Esther? Consider who prepared the banquet? Several verses to consider; hopefully you will see footprints emerge.
King: God, the Father. The Son at His right hand.
Queen: The city(Spirit) from above: The mother of us all.
Esther 3:8-9,13
[8] And Haman said unto king Ahasuerus, There is a certain people scattered abroad and dispersed among the people in all the provinces of thy kingdom; and their laws are diverse from all people; neither keep they the king's laws: therefore it is not for the king's profit to suffer them.(how long must I suffer you?) [9] If it please the king, let it be written that they may be destroyed: and I will pay ten thousand talents of silver to the hands of those that have the charge of the business, to bring it into the king's treasuries.
13] And the letters were sent by posts into all the king's provinces, to destroy, to kill, and to cause to perish, all Jews, both young and old, little children and women, in one day, even upon the thirteenth day of the twelfth month, which is the month Adar, and to take the spoil of them for a prey.
Esther 4:2,4
[2] And came even before the king's gate: for none might enter into the king's gate clothed with sackcloth.
4] So Esther's maids and her chamberlains came and told it her. Then was the queen exceedingly grieved; and she sent raiment to clothe Mordecai, and to take away his sackcloth from him: but he received it not.
Esther 5:1,4,12-13
[1] Now it came to pass on the third day, that Esther(that new Jerusalem, Spirit from above) put on her royal apparel , and stood in the inner court of the king's house, over against the king's house: and the king sat upon his royal throne in the royal house, over against the gate of the house.
4] And Esther answered, If it seem good unto the king, let the king and Haman come this day unto the banquet that I have prepared for him.
12] Haman said moreover, Yea, Esther the queen did let no man come in with the king unto the banquet that she had prepared but myself; and to morrow am I invited unto her also with the king. [13] Yet all this availeth(profit) me nothing, so long as I see Mordecai the Jew sitting at the king's gate.
Esther 6:9
[9] And let this apparel and horse be delivered to the hand of one of the king's most noble princes, that they may array the man withal whom the king delighteth to honour, and bring him on horseback through the street of the city, and proclaim before him, Thus shall it be done to the man whom the king delighteth to honour.
Esther 7:10
[10] So they hanged Haman on the gallows that he had prepared for Mordecai. Then was the king's wrath pacified.
Esther 8:1-2,6-7,15-17
[1] On that day did the king Ahasuerus give the house of Haman the Jews' enemy unto Esther the queen. And Mordecai came before the king; for Esther had told what he was unto her. [2] And the king took off his ring, which he had taken from Haman, and gave it unto Mordecai. And Esther set Mordecai over the house of Haman.
[6] For how can I endure to see the evil that shall come unto my people? or how can I endure to see the destruction of my kindred? [7] Then the king Ahasuerus said unto Esther the queen and to Mordecai the Jew, Behold, I have given Esther the house of Haman, and him they have hanged upon the gallows, because he laid his hand upon the Jews.
[15] And Mordecai went out from the presence of the king in royal apparel of blue and white, and with a great crown of gold, and with a garment of fine linen and purple: and the city of Shushan rejoiced and was glad. [16] The Jews had light, and gladness, and joy, and honour. [17] And in every province, and in every city, whithersoever the king's commandment and his decree came, the Jews had joy and gladness, a feast and a good day. And many of the people of the land became Jews; for the fear of the Jews fell upon them.
Esther 9:1-2
[1] Now in the twelfth month, that is , the month Adar, on the thirteenth day of the same, when the king's commandment and his decree drew near to be put in execution, (very important) in the day that the enemies of the Jews hoped to have power over them, (though it was turned to the contrary, that the Jews had rule over them that hated them [2] The Jews gathered themselves together in their cities throughout all the provinces of the king Ahasuerus, to lay hand on such as sought their hurt: and no man could withstand them; for the fear of them fell upon all people.
Esther 10:3
[3] For Mordecai the Jew was next unto king Ahasuerus, and great among the Jews, and accepted of the multitude of his brethren, seeking the wealth of his people, and speaking peace to all his seed.
Isaiah 59:21
[21] As for me, this is my covenant with them, saith the Lord ; My spirit that is upon thee, and my words which I have put in thy mouth, shall not depart out of thy mouth, nor out of the mouth of thy seed, nor out of the mouth of thy seed's seed, saith the Lord , from henceforth and for ever.
