The opening Pesukim of the Parsha speak about the Brit between Hashem and the Avot. It seems that after four hundred years of being in Egypt, Bnai Yisrael will automatically be saved without having to do anything to initiate the Geula. However, maybe it is not so simple, and perhaps really Bnai Yisrael have to start the process.
Parshat Shemot ends with Moshe receiving two commandments from Hashem. The first was to notify Bnai Yisrael that Hashem will bring them to Eretz Yisrael, while the second was and to demand that Pharo let Bnai Yisrael go to the Midbar for three days to worship Hashem. Bnai Yisrael were very happy about this until Pharo added to their work, which made them complain to Moshe that he just made things worse for them. In the beginning of Vaera Hashem responds to this complaint by reminding Moshe of the Brit and giving him a third commandment of telling Bnai Yisrael “I am Hashem and I will take them out…”(6:6). This third commandment, can not simply be for reassurance, as Bnai Yisrael “did not listen to Moshe” (6:9) so it must have some greater significance.
To understand the extra significance the Pesukim must be analyzed. Bnai Yisrael’s rejection (of Moshe’s third commandment) is stated as “Velo Shamu El Moshe” (6:9). “Velo Shamu” can be translated in a number of ways. It can mean they did not hear (physically), they didn’t understand, they didn’t believe or they didn’t obey. The first two (hear and understand) don’t make sense in context, while the third (belief) could fit. However, then the Torah probably would have written “Velo Heeminu” as it did in 4:31. To obey (listen to it) also seems difficult because there doesn’t seem to be anything to obey. All Moshe told them is that Hashem will save them. A recurrence of this word a few Pesukim later can help explain its meaning. Pasuk 12 says that even Bnai Yisrael “Lo Shamu Eilai Veich Yishmaeini Pharo,” “they didn’t obey me, so how will Pharo?” Clearly “Shamu” in reference to Pharo means to obey (obey Hashem’s command to let Bnai Yisrael go). So for the Kal Vechomer of the Pasuk to make sense the “Shamu” in reference to Bnai Yisrael must also mean to obey. (The Pasuk only makes sense when it is interpreted as: why will Pharo obey (listen to) me if even Bnai Yisrael don’t obey me). Thus the previous difficulty with the translation of “Shamu” meaning “to obey” must be reconsidered; there must really be something which requires adherence (something to obey).
The words “Ani Hashem” recurs many times in Pesukim 6:2,6,7,8. The Torah must be implying that there is indeed a commandment not just to intellectually recognize Hashem, but to internalize His status of “Ani Hashem Elokeichem.” The first of the Aseret Hadibrot can be understood as this commandment to internalize Hashem’s per and to obey any of His laws. Thus the third commandment to Moshe was to teach Bnai Yisrael to accept Hashem in order for them to do Teshuva and bring the Geula. This explanation is proven from Yechezkel 20:5-8, where Yechezkel is telling some Zekeinim that Bnai Yisrael weren’t always good before Yetziat Mitzrayim. Hashem told Bnai Yisrael that “Ani Hashem Elokeichem” but they rebelled and said, “Lo Shamu Eilai” (there was rebellion involved in that they did not accept Hashem internally). Finally, Pasuk 13, Hashem’s response to Moshe can be explained. Moshe must tell both Pharo and Bnai Yisrael to let Bnai Yisrael leave Mitzrayim. Pharo was asked to permit Bnai Yisrael to leave, and Bnai Yisrael were told to initiate the Geula by internalizing Hashem and doing Teshuva.