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.
[AD 856] Rabanus Maurus on Esther 3:7-15
The fact that the twelfth month, which is called Adar, was chosen for the destruction of Israel after casting lots is not with its own spiritual meaning. It is referring, in fact, to the grace of Christ which has been prepared for the faithful in the fullness of time when the faithful will undergo a fierce persecution in the world in the last days. And writing about this to Timothy, the teacher of the Gentiles says, “You must understand this, that in the last days distressing times will come. For people will be lovers of themselves, lovers of money, boasters, arrogant, abusive, disobedient to their parents, ungrateful, unholy, inhuman, implacable, slanderers, profligates, brutes, haters of good, treacherous, reckless, swollen with conceit, lovers of pleasure rather than lovers of God, holding the outward form of godliness but denying its power.” And the Lord himself says in the Gospel, “And this gospel of the kingdom will be proclaimed throughout the world, as a testimony to all the nations; and then the end will come.” And a bit further: “For at that time there will be great suffering, such as has not been from the beginning of the world until now, and never will be.”

[AD 420] Jerome on Esther 3:13
[Daniel 7:5] "And behold another beast like a bear stood up on one side; and there were three rows in his mouth and in his teeth; and they said to him: 'Arise up and devour flesh in abundance.'" The second beast resembling a bear is the same as that of which we read in the vision of the statue (2:32): "His chest and arms were of silver." In the former case the comparison was based on the hardness of the metal, in this case on the ferocity of the bear. For the Persian kingdom followed a rigorous and frugal manner of life after the manner of the Spartans, and that too to such an extent that they used to use salt and nasturtium-cress in their relish. Let us consult the record of the childhood of Cyrus the Great (i.e., "The Education or Training" of Cyrus). And as for the fact that the bear is said to have "stood up on one side," the Hebrews interpret it by saying that the Persians never perpetrated any cruelty against Israel. Hence they are described in the Prophecy of Zechariah also as white horses (Zechariah 1:7-11). But as for the three rows or ranks that were in his mouth and between his teeth, one authority has interpreted this to mean that allusion was made to the fact that the Persian kingdom was divided up among three princes, just as we read in the sections dealing with Belshazzar and with Darius that there were three princes who were in charge of the one hundred and twenty satraps. But other commentators affirm that these were three kings of the Persians who were subsequent to Cyrus, and yet they fail to mention them by name. But we know that after Cyrus's reign of thirty years his son Cambyses ruled among the Persians, and his brothers the magi, and then Darius, in the second year of whose reign the rebuilding of the Temple was commenced at Jerusalem. The fifth king was Xerxes, the son of Darius; the sixth was Artabanus; the seventh, Artaxerxes who was surnamed Makrokheir, that is Longimanus ("Long-handed"); the eighth, Xerxes; the ninth, Sogdianus; the tenth, Darius surnamed Nothos ("Bastard"); the eleventh, the Artaxerxes called Mnemon, that is, "The Rememberer"; the twelfth, the other Artaxerxes, who himself received the surname of Ochus; the thirteenth, Arses, the son of Ochus; and the fourteenth, Darius the son of Arsamus, who was conquered by Alexander, the king of the Macedonians. How then can we say that these were three kings of the Persians? Of course we could select some who were especially cruel, but we cannot ascertain them on the basis of the historical accounts. Therefore the three rows in the mouth of the Persian kingdom and between its teeth we must take to be the three kingdoms of the Babylonians, the Medes, and the Persians, all of which were reduced to a single realm. And as for the information, "And thus they spake to him: 'Devour flesh in abundance,'" this refers to the time when in the reign of the Ahasuerus whom the Septuagint calls Artaxerxes, the order was given, at the suggestion of Haman the Agagite, that all the Jews be slaughtered on a single day (Esther 3:13). And very properly, instead of saying, "He was devouring them" the account specifies, "Thus they spake unto him..." This shows that the matter was only attempted, and was by no means ever carried out.

[AD 856] Rabanus Maurus on Esther 3:13
Nor is it merely a straightforward fact that it was the twelfth month of the year, which is called Adar, that was set aside by lot for the murder of Israel; it signifies rather that the grace of Christ, which has been entrusted to the faithful in the fullness of time, is going to experience a harsh persecution in this world in the last days, carried out upon the faithful. This is what the teacher of the nations is also writing about when he says to Timothy: “And let it be known that in the last days we will face dangerous times; and men will be lovers of themselves, greedy, arrogant, proud, blasphemers, disobedient to their parents, ungrateful, wicked, emotionless, implacable, slanderers, unrestrained, harsh, without kindness, treacherous, reckless, bombastic, loving their pleasures more than they do God; and though they will have the appearance of righteousness, they will deny its power.” Hence the Lord also says in the Gospel: “This evangel of the kingdom will be preached throughout the whole world as a testimony to all the nations, and then the end will arrive” (Matthew 24). And a bit after that: “Then there will be great tribulation, of a sort there has not been since the beginning of the world till now; but it will not happen unless those days have been cut short” (ibid.).