Oznayim la'Torah: Perhaps it is because they did not rebel constanrly, as implied by the Pasuk.
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since we find many good deeds that they performed during Moshe's tenure as leader - 'Na'aseh ve'Nishma', Kabalas ha'Torah, building the Mishkan.
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See Oznayim la'Torah, who elaborates, and conc;udes that, minus the 'Mem', the word reads 'Morim', teachers - because they demonstrated to the world the Greaness of Hashem, like we find regarding Yisro and Rachav ha'Zonah and the two spies - Calev and Pinchas.
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Why did Moshe insert here the words "mi'Yom Da'ati Eschem"?
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Ramban: It hints at the times that they complained before Matan Torah.
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Hadar Zekenim: It refers to the time when Moshe said to Dasan "Lamah Sakeh Re'echa"
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, and Dasan informed on him.
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