Why does the Torah suddenly get involved in these three Shevotim (Reuven, Shimon, and Levi)? It says וַיַּרְא ה' כִּי שְׂנוּאָה לֵאָה וַיִּפְתַּח אֶת רַחְמָהּ Hashem saw that Leah was unloved, so He gave her a child. The Alter of Kelm Zatzal says that the reason why Leah was Zoche was only because she was a: שְׂנוּאָה reject, not because of her Tzidkus or Tefilos. Her first three children were named in appreciation for them, since they caused her husband to love her.
Especially Levi (which means: הַפַּעַם יִלָּוֶה אִישִׁי אֵלַי my husband will now become attached to me), since he caused an action of love from Yaakov, since now he would actually walk together with Leah. For good reason it was Shevet Levi that produced our redeemer, Moshe. It says: וַיָּקֻצוּ מִפְּנֵי בְּנֵי יִשְׂרָאֵל the Yidden were like thorns in the eyes of the Mitzri'im (Rashi).
And: הָאֱלֹקִים יְבַקֵּשׁ אֶת נִרְדָּף Koheles 3:15 Hashem sticks up for the victim, even if the victim is a Rasha and the persecutor is a Tzaddik. (Chazal). Just as Leah was Zoche, not because of her Zechusim, but only because she was a: שְׂנוּאָה reject, the same with the Yidden; since they were: שְׂנוּאִים hated, they would be saved from the Mitzri'im.
Not because of their Zechusim. In fact, Klal Yisroel was: עֵרֹם וְעֶרְיָה Yechezkel 16:7 completely stripped from any Ruchaniyus and Zechusim. They were steeped in: מ"ט שַעֲרֵי טוּמְאָה the 49th level of Tum'ah, and Chazal say: הַלָּלוּ עוֹבְדֵי עֲבוֹדָה זָרָה לָהַוְלוּ עוֹבְדֵי עֲבוֹדָה זָרָה the Yidden worshipped Avoda Zara no less than the Mitzri'im. Before the Torah tells the story of Yetzias Mitzrayim, it states the products (i.e., the sons) of the rejected Leah, who were produced because of her: שְׂנוּאָה reject situation. Shevet Levi forever remains the Shtempel that finalized and totally rescued a Sin'ah situation. And Moshe, Ahron & Miriam (her great members) would be responsible for rescuing Klal Yisroel from the cruel: וַיָּקֻצוּ מִפְּנֵי בְּנֵי יִשְׂרָאֵל harassment and all the slavery.
Notice how Moshe is always rescuing people (in Mitzrayim twice; and then in Midyan he rescued the daughters of Yisro). The very existence of Shevet Levi was a final gesture by Hashem to save Leah from being a: שְׂנוּאָה reject. Look how Moshe is always stopping fights, and preventing people from hurting each other.
The true Levi remembers the source of his Neshama, which was Hashem ending the: שְׂנוּאָה rejection of Leah problem. Moshe’s name should have been: וּשמָי (drawn from water) since he was saved from water, but since he was saved, his job now is to save others, therefore his name is Moshe. (Seforno)
