A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
est 4:1MORDECAI AND THE JEWS MOURN. (Est 4:1-14)
When Mordecai perceived all that was done--Relying on the irrevocable nature of a Persian monarch's decree (Dan 6:15), Hamman made it known as soon as the royal sanction had been obtained; and Mordecai was, doubtless, among the first to hear of it. On his own account, as well as on that of his countrymen, this astounding decree must have been indescribably distressing. The acts described in this passage are, according to the Oriental fashion, expressive of the most poignant sorrow; and his approach to the gate of the palace, under the impulse of irrepressible emotions, was to make an earnest though vain appeal to the royal mercy. Access, however, to the king's presence was, to a person in his disfigured state, impossible: "for none might enter into the king's gate clothed with sackcloth." But he found means of conveying intelligence of the horrid plot to Queen Esther.
est 4:4Then was the queen . . . grieved; and . . . sent raiment to . . . Mordecai--Her object in doing so was either to qualify him for resuming his former office, or else, perhaps, of fitting him to come near enough to the palace to inform her of the cause of such sudden and extreme distress.
est 4:5Then called Esther for Hatach, one of the king's chamberlains, whom he had appointed to attend upon her--Communication with the women in the harem is very difficult to be obtained, and only through the medium of the keepers. The chief eunuch receives the message from the lips of the queen, conveys it to some inferior office of the seraglio. When the commission is executed, the subaltern communicates it to the superintendent, by whom it is delivered to the queen. This chief eunuch, usually an old man who has recommended himself by a long course of faithful service, is always appointed by the king; but it is his interest, as well as his duty, to ingratiate himself with the queen also. Accordingly, we find Hatach rendering himself very serviceable in carrying on those private communications with Mordecai who was thereby enabled to enlist Esther's powerful influence.
est 4:8charge her that she should go in unto the king--This language is exceedingly strong. As it can scarcely be supposed that Mordecai was still using authority over Esther as his adopted daughter, he must be considered as imploring rather than commanding her, in the name of her brethren and in the name of her God, to make a direct appeal to the feelings of her royal husband.
est 4:11whosoever, whether man or woman, shall come unto the king into the inner court, who is not called--The Persian kings surrounded themselves with an almost impassable circle of forms. The law alluded to was first enacted by Deioces, king of Media, and afterwards, when the empires were united, adopted by the Persians, that all business should be transacted and petitions transmitted to the king through his ministers. Although the restriction was not intended, of course, to apply to the queen, yet from the strict and inflexible character of the Persian laws and the extreme desire to exalt the majesty of the sovereign, even his favorite wife had not the privilege of entree, except by special favor and indulgence. Esther was suffering from the severity of this law; and as, from not being admitted for a whole month to the king's presence, she had reason to fear that the royal affections had become alienated from her, she had little hope of serving her country's cause in this awful emergency.
est 4:13Then Mordecai commanded to answer Esther--His answer was to this effect, that Esther need not indulge the vain hope she would, from her royal connection, escape the general doom of her race--that he (Mordecai) confidently believed God would interpose, and, if not through her, by some other deliverer, save His people; but that the duty evidently devolved on her, as there was great reason to believe that this was the design of Providence in her elevation to the dignity of queen, and therefore that she should go with a courageous heart, not doubting of success.
est 4:16so will I go in unto the king, which is not according to the law--The appeal of Mordecai was irresistible. Having appointed a solemn fast of three days, she expressed her firm resolution to make an appeal to the king, though she should perish in the attempt.
I . . . and my maidens--It is probable that she had surrounded herself with Jewish maidens, or women who were proselytes to that religion.