1)
What does the Torah mean when it writes "ve'es Mishmeres B'nei Yisrael"?
1.
Rashi: It means that, strictly speaking, all of Yisrael should have assisted Aharon and his sons to guard the Mishkan, but the Levi'im were designated to do so on their behalf. 1
2.
Seforno: It means that, strictly speaking, all of Yisrael should have assisted Aharon and his sons to transport the Mishkan and to sing during the Avodah, 2 tasks that were now handed over to the Levi'im to fulfil.
