(lots), the annual festival instituted to commemorate the preservation of the Jews in Persia from the massacre with which they were threatened through the machinations of Haman. (Esther 9:1) ... It was probably called Purim by the Jews in irony. Their great enemy Haman appears to have been very superstitious, and much given to casting lots. (Esther 3:7) They gave the name. Purim, or "Lots," to the commemorative festival because he had thrown lots to ascertain what day would be suspicious for him to carry into effect the bloody decree which the king had issued at his instance. (Esther 9:24) The festival lasted two days, and was regularly observed on the 14th and 15th of Adar. According to modern custom, as soon as the stars begin to appear, when the 14th of the month has commenced, candles are lighted up in token of rejoicing, and the people assemble in the synagogue. After a short prayer and thanksgiving, the reading of the book of Esther commences. The book is written in a peculiar manner, on a roll called "the Roll" (Megillah). When the reader comes to the name of Haman, the congregation cry out, "May his name be blotted out," or, "Let the name of the ungodly perish." When the Megillah is read through, the whole congregation exclaim, "Cursed be Haman; blessed be Mordecai; cursed be Zoresh (the wife of Haman); blessed be Esther; cursed be all idolaters; blessed be all Israelites, and blessed be Harbonah who hanged Haman." In the morning service in the synagogue, on the 14th, after the prayers, the passage is read from the law, (Exodus 17:8-16) which relates the destruction of the Amalekites, the people of Agag, (1 Samuel 15:8) the supposed ancestor of Haman. (Esther 3:1) The Megillah is then read again in the same manner. The 14th of Adar, as the very day of the deliverance of the Jews, is more solemnly kept than the 13th; but when the service in the synagogue is over, all give themselves up to merry making.
Purim
Mordecai and Esther sent letters to every province asking the Jews to keep two days each year. The reason was a reversal. Haman, “the enemy of all the Jews”, had cast Pur, that is, the lot, to choose a day for their destruction. Instead the month was “turned unto them from sorrow to joy, and from mourning into a good day.” The feast took its name from Pur, and the chapter says the days were to be remembered in every family and every city. The passage is about gladness, rest and remembering. Read Esther 9:20-32, then the earlier chapters for the story behind it.
13 verses
Esther
And Mordecai wrote these things, and sent letters unto all the Jews that were in all the provinces of the king Ahasuerus, both nigh and far,
To stablish this among them, that they should keep the fourteenth day of the month Adar, and the fifteenth day of the same, yearly,
As the days wherein the Jews rested from their enemies, and the month which was turned unto them from sorrow to joy, and from mourning into a good day: that they should make them days of feasting and joy, and of sending portions one to another, and gifts to the poor.
And the Jews undertook to do as they had begun, and as Mordecai had written unto them;
Because Haman the son of Hammedatha, the Agagite, the enemy of all the Jews, had devised against the Jews to destroy them, and had cast Pur, that is, the lot, to consume them, and to destroy them;
But when Esther came before the king, he commanded by letters that his wicked device, which he devised against the Jews, should return upon his own head, and that he and his sons should be hanged on the gallows.
Wherefore they called these days Purim after the name of Pur. Therefore for all the words of this letter, and of that which they had seen concerning this matter, and which had come unto them,
The Jews ordained, and took upon them, and upon their seed, and upon all such as joined themselves unto them, so as it should not fail, that they would keep these two days according to their writing, and according to their appointed time every year;
And that these days should be remembered and kept throughout every generation, every family, every province, and every city; and that these days of Purim should not fail from among the Jews, nor the memorial of them perish from their seed.
Then Esther the queen, the daughter of Abihail, and Mordecai the Jew, wrote with all authority, to confirm this second letter of Purim.
And he sent the letters unto all the Jews, to the hundred twenty and seven provinces of the kingdom of Ahasuerus, with words of peace and truth,
To confirm these days of Purim in their times appointed, according as Mordecai the Jew and Esther the queen had enjoined them, and as they had decreed for themselves and for their seed, the matters of the fastings and their cry.
And the decree of Esther confirmed these matters of Purim; and it was written in the book.
From Smith's Bible Dictionary
William Smith, 1884