The Vilna Gaon writes that Mordechai did not get up as if Haman were not even there.
The Ohel Moshe reminds us that Nefesh HaChaim (3:12) writes that a powerful spiritual power we have is to internalize the idea that no influence can affect us besides H-Shem. Mordechai’s believing this is one reason he refuses to even rise for Haman.
The Maharal writes the two actions of standing and stirring refer to Mordechai giving no sign of respect to either Haman, nor the idol he had constantly about him. He quotes the Midrash (Esther Rabbah 7:8) that Mordechai felt Haman made himself into an idolatry. In other words, borrowing a phrase from Yeshaya (2:24) such a person has “his soul in his nose,” or considers his own self-aggrandizement before anything else. For this self-worship is what Mordechai could not stir.
Rebbetzin Heller writes that when the Alter Rebbe of Lubavitch was is Russia, he quoted a Talmud (Sanhedrin 74a-b) that there are three things for which Jews should give up their lives to avoid transgressing. Put simply, these three “cardinal sins” are idolatry, adultery, and murder. However, that is only true under regular circumstances. However, if a nation attempts to destroy Judaism altogether, even the “smallest” of sins cannot be committed under threat of death. Therefore, in communist Russia too, where their laws added up to a struggle against Judaism, all of their laws could be ignored.
In an interesting gematria, the phrase v’lo kam v’lo za (“he did not rise and he did not stir”) (6+30+1+100+40+6+30+1+7+70=291) less the two mentions of v’lo (“and he did not”) (6+30+1=37×2=74) is equivalent to 217, the numerical value of eretz (“land”) (1+200+90=291). Perhaps this indicates that Mordechai’s refusal to do these actions helped the Jews merit re-entry into the Land of Israel in the following Persian reigns.
The Vilna Gaon says that Mordechai knew that Esther, being a righteous woman, never voluntarily submitted to Achashverosh carnally. In addition to the fact that he was a gentile, we learned earlier that Esther was married to Mordechai before she was forcibly removed from his home. Accordingly, Esther would need the force of a command to submit to Achashverosh voluntarily. There is a story told of a community rav who was in a situation in which circumstances were such that he had to build a synagogue where a mikvah once stood. Otherwise, his congregation would have no home. Knowing that Halacha (see Igros Moshe, Choshen Mishpat I, Siman 40) does not allow for a shul to be built in such a place, he asked the Chazon Ish for advice. The Chazon Ish reportedly told the rav that he was right, and that building the shul in such a location would earn him punishment in this world and the next. Nevertheless, he still had to do it. His congregation needed a home, and, as a leader, he had the responsibility to accept punishment for their benefit. Here, too, Esther was required to perform this sin for the benefit of the entire nation. Esther would not have gone to Achashverosh voluntarily.
R’ Moshe Dovid Valle quotes the verse in Koheles (3:7) that there is “a time to be silent, and a time to speak.” In other words, Mordechai was telling Esther that there was a time when he commanded her to remain silent regarding her ancestry (see 2:10); now, he was rescinding that command and telling her to speak.
R’ Dovid Feinstein gives another reason why Esther needed to be commanded. Quoting a Rashi in Vayikra 6:2 (in Parshas Tzav), he writes that the word, “tzav” (“command”) is only used when the person performing the action is reluctant to do it because there is something they stand to lose. Here, Mordechai has to command Esther because he realizes her self-sacrifice. Recalling that Mordechai is speaking to Hasach (Daniel) that he has to command Esther because he is a greater Torah scholar. As such, Esther would be more likely to listen to the command.