Commentators offer an array of reasons why Esther might have concealed her nationality. On one end of the spectrum, R. Reggio asserts that Esther kept her identity a secret for her own personal benefit, assuming that hiding knowledge of her lowly Jewish roots would promote her chances of becoming queen. While this approach suggests that she did this for her own prestige, Lekah tov and Ralbag, on the other end of the spectrum, suggest that her motives were altruistic. Esther hoped the secret would aid her in becoming queen so that she would be best positioned to aid her nation when needed.
A middle position assumes, instead, that Esther's motives were religious in nature. According to Rashi she did not want to become queen at all, as this would make leading a religious life extremely difficult. She hid her royal lineage, which would have increased her chances, so as to prevent this. Ibn Ezra instead focuses on the period after becoming queen, suggesting that Esther realized that observance in the palace would be easier if no one was aware of her religion.
Personal Gain
Esther kept her identity a secret so as to facilitate her being chosen as queen.
אֶת עַמָּהּ וְאֶת מוֹלַדְתָּהּ – What did Esther not tell?
Nationality – According to most of these exegetes, the words "עַמָּהּ וְמוֹלַדְתָּהּ" refer to Esther's Jewish nationality. Esther did not want others to know that she was Jewish since the Jewish nation was degraded in the eyes of the Persians. As such, the knowledge might lower her chances of being chosen.
Exilic origins – The opinion brought in Ibn Ezra and R. Reggio emphasize instead that she wanted to conceal the fact that she came from exile ("מוֹלַדְתָּהּ") since this, rather than her Jewish roots,1 was the potential source of humiliation.2
Esther and Mordechai's religious identity – Most of the commentators do not address the question, but R. Y"S Reggio points out that Mordechai and Esther do not seem overly concerned with observing the commandments. Thus, Mordechai never warns Esther to uphold belief in one God and reject Persian polytheism, nor to try and keep the laws of kashrut.3 Instead, he does all in his power to get her to become queen, despite the fact that it will make observance more difficult.4
Why become queen? As opposed to the approach "agent of salvation" below, this position assumes5 that Esther wanted to become queen not for altruistic reasons but for the personal prestige and honor that accompanied the position.6
"וַתִּלָּקַח אֶסְתֵּר אֶל בֵּית הַמֶּלֶךְ" – The passive form of these words is difficult for this position as it makes it sound as if Esther was taken against her will, while these commentators assert that she was actively trying to be chosen. They would likely explain that no one went on their own to the palace; all candidates were brought there by the king's officers. Thus, the language of "וַתִּלָּקַח" does not necessarily connote a forceful taking against one's will.
"לֹא בִקְשָׁה דָּבָר" – These words, too, suggest a passivity on the part of Esther which does not fit the portrait of one who wishes to be chosen as queen. Y. Hazony,7 though, suggests that in reality this was part of Esther's strategy. The verse points out that Esther did not request anything on her own, but only, "אֲשֶׁר יֹאמַר הֵגַי סְרִיס הַמֶּלֶךְ שֹׁמֵר הַנָּשִׁים". Esther realized that Hegai, a professional in charge of the king's harem, knew best what it was that the king would want and thus followed his advice in all.
Until when did Esther keep the secret?
Until the party – R. Yosef Kara, Rashbam, and R. Reggio all claim that Esther hid her identity both before and after her coronation, presumably, lest it cause her to lose the crown.
Until her position was secure – Alternatively, this position could posit that the secret was necessary only during the pageant itself, to ensure that she was not automatically passed over due to her religion or foreign status.8 If so, the repeated mention of the fact of concealment after her coronation would need to be read as a summary statement for the chapter9 or as related specifically to the second gathering of virgins, when the competition was renewed.10
Revealing the secret – R. Avigdor Kohen Tzedek questions this approach from Achashverosh's attitude upon Esther's revelation of her identity. If her Judaism was abhorrent in his eyes, then it is not clear why Esther thought that revealing the fact should save her or her nation. It should have been a cause for her rejection! This position might respond that, by that point, Esther had completely won over Achashverosh's affection and he no longer cared about her origins.11
Evaluating the decision – Ibn EzraEsther Version A 2:9About R. Avraham ibn Ezra suggests that if Mordechai and Esther were really motivated simply by a desire that Esther become queen, their actions should be condemned. If embarrassment over their Judaism further played a role, the actions are even more problematic. This is especially true considering that, had Esther's nationality been known, it is possible that Haman would never have issued his edict.12
Religious Observance
The secrecy surrounding Esther's identity was related to her religious observance. Commentators subdivide regarding whether her purpose was to avoid compromising her faith by trying not to become queen at all or to overcome the difficulties in observance after having been chosen.
Avoid Becoming Queen
Esther concealed her identity in order to reduce her chances of becoming queen and thus avoid the accompanying difficulties this might entail for Torah observance.
Esther and Mordechai's religious identity – These exegetes maintain that Mordechai and Esther were observant Jews13 who were upset by the concept that Esther should marry a Persian king14 and be forced into a position where her faith and observance would be compromised.
אֶת עַמָּהּ וְאֶת מוֹלַדְתָּהּ – What did Esther not tell? Rashi and Rid maintain that Esther was of royal lineage, being a descendant of King Shaul. It was this lineage that Esther attempted to conceal as it would make her a more appealing candidate. Though the word "מוֹלַדְתָּהּ" could support this reading, it would be difficult to say that the word "עַמָּהּ" is limited to family status.
Was Esther from Shaul's family? Rashi asserts that "אִישׁ יְמִינִי" means that Mordechai was from the tribe of Binyamin, and he apparently assumes that the "קִישׁ" who is mentioned in Mordechai's genealogy is the same as the father of Shaul. Ibn EzraEsther Version A 2:5About R. Avraham ibn Ezra questions that if the verses wanted to highlight that Mordechai was a descendant of Shaul, it is strange that they would skip generations to mention Kish by name but not Shaul.
"וַתִּלָּקַח אֶסְתֵּר אֶל בֵּית הַמֶּלֶךְ" and "לֹא בִקְשָׁה דָּבָר" – These verses support the notion that Esther was taken by force and preferred not to be chosen.
Until when did Esther keep the secret?
Concealed until the party – Rashi and Rid follow the simple reading of the verses which suggest that Esther continued to conceal her identity even after she was chosen. This is somewhat difficult for this position, considering that such secrecy no longer served any purpose. Rashi suggests that once Esther was taken, Mordechai understood that she was meant to be a tool for the salvation of Israel.15 If so, it is possible that he thought that somehow continuing to hide her identity would help serve that purpose.16
Revealed after coronation – Alternatively, it is possible that Esther did not continue to hide her identity after being chosen. As mentioned above, Esther 2:20 (the second mention of Esther hiding her identity) would then be read as a summary statement recapping what previously happened,17 rather than a statement of what Esther did throughout her reign. In addition, to make sense of the end of the story, one would have to posit that Achashverosh was unaware of the identity of the nation which Haman wanted to destroy, while being fully aware that Esther was Jewish.18
Evaluating the decision – This position views Esther's motives positively, even if they were ineffective.
Enable Torah Observance
Mordechai felt that Esther would be better able to keep Hashem's commandments if her Judaism was not known.
Esther and Mordechai's religious identity – This position is based on the assumption that the two were observant Jews. Ibn Ezra identifies Mordechai with the person by the same name listed as one of those who followed Zerubavel to Israel,19 suggesting that he was not a layman, but rather a prominent Jew.
Why would observance be easier?
According to Ibn Ezra, if Esther's religion were known the king would have actively forced her to transgress commandments, such as eating non-kosher and the like. If no one knew, though, they might not notice if she observed mitzvot in secret.
The Akeidat Yitzchak instead suggests that the secret was meant to ensure that Esther did not fall into a situation in which the law would mandate that she give up her life rather than transgress a law. Had her Judaism been public and then Achashverosh demanded of her to violate it, the laws of "יהרג ואל יעבר" would have applied.
Did the Jews know Esther's identity? According to the Akeidat Yitzchak, Esther would have had to hide her identity even from the Jews. Considering that she was taken from the house of Mordechai who was presumably known to the Jews, this seems somewhat difficult.20 Ibn Ezra could instead posit that the Jews knew Esther's identity but did not reveal it.
אֶת עַמָּהּ וְאֶת מוֹלַדְתָּהּ – What did Esther not tell? Both Ibn Ezra and the Akeidat Yitzchak suggest that these terms refer to Esther's Jewish roots and it was this that she concealed.
"וַתִּלָּקַח אֶסְתֵּר אֶל בֵּית הַמֶּלֶךְ" and "לֹא בִקְשָׁה דָּבָר" – This position would point to these verses as evidence that Esther was taken by force and did not willingly go to the palace. Moreover, once there she did not ask for anything that might lead her to be chosen.
Until when did Esther keep the secret? These commentators maintain that Esther continued hiding her identity throughout her reign, revealing it only at the second party..
National Interests
Esther was thinking about the good of the nation as a whole when she decided to conceal her background.
Agent of Salvation
Esther hid her religious identity so that she would be best positioned to save her nation.
Become queen – The Lekach Tov and Ralbag maintain that Esther concealed her identity so that she would be chosen by the king and be able to aid the Jews from that position of power.22 Had Achashverosh known her "lowly" nationality he would have scorned and rejected her out of hand.
Privy to secrets – The Rokeach, instead, maintains that were Esther's identity known, everyone would have made sure to conceal from her any potential plots against the Jews. If she was believed to be a Gentile, on the other hand, she would be privy to such information.
Esther and Mordechai's religious identity – These commentators assume that Mordechai and Esther were religious Jews. It is also possible, however, that they might have had strong cultural and national ties to their people, but were not particularly observant. This might explain why the Megillah makes no mention of prayer or any attempts to observe Jewish laws. Moreover, it explains why the two see the potential benefits of Esther becoming queen as outweighing the problem of compromising religious observance.
"וַתִּלָּקַח אֶסְתֵּר אֶל בֵּית הַמֶּלֶךְ" – The Lekach Tov and Ralbag assume that Esther desired to become queen,23 and they thus need to explain the passive form of the verb "וַתִּלָּקַח". Like the first approach above, they would presumably suggest that all the women were actively taken (but not necessarily forced) to the palace by the officers, regardless of whether they would have gone on their own or not.
"לֹא בִקְשָׁה דָּבָר" – As above, the Lekach Tov and Ralbag might suggest that Esther asked for nothing on her own, instead putting her trust in Hegai's abilities. She assumed that he would know best what the king desired, making her more likely to be chosen.
Until when did she keep the secret? Esther first revealed her identity at the second party, when the revelation served to save her nation.
Evaluating the decision – was secrecy a good idea? R. Reggio questions this approach from the fact that hiding Esther's identity never served to help the Jews; it was only upon its revelation that they were saved. In fact, had Esther revealed her identity from the very beginning, it is possible that Haman would never even have hatched his plan!24
Other political positioning – Y. Hazony25 suggests that Mordechai's betraying of Bigtan and Teresh was similarly motivated by political positioning. Both he and Esther realized that active support of the despot, even if meant keeping secrets or compromising morality, was the best way to help their nation.
Decreased Danger
Mordechai and Esther feared that were Achashverosh to get angry at Esther, he would take it out on the entire Jewish nation. To prevent this, Esther did not tell the king to which nation she belonged.
Esther and Mordechai's religious identity – These sources all assume that Mordechai and Esther were observant Jews.
"וַתִּלָּקַח אֶסְתֵּר אֶל בֵּית הַמֶּלֶךְ" and "לֹא בִקְשָׁה דָּבָר" – According to these sources, Esther did not wish to be chosen as queen and even hid from the officers so that she would not be taken. She viewed becoming queen of the unstable and wrathful Achashverosh as a potential source of danger to the Jewish nation.27 Both the passive form of "וַתִּלָּקַח" and the fact that Esther did not request anything during her preparations may support this reading.
Until when did she keep the secret? Esther revealed her identity only when she saw that the nation was endangered from another source and that the revelation might be more helpful than keeping it a secret.