1)
What did Moshe mean when he instructed Yisrael to be silent?
1.
Rashi (to Shir ha'Shirim 1:9): He meant that they should stop Davening. 1
2.
Targum Yonasan: Refer to 14:13:1:1 , regarding the fourth group.
1
And begin moving forward, as the following Pasuk states (14:15).
2)
How will we reconcile this Pasuk (Hashem asking Yisrael not to participate in the battle against the Egyptians) with the principle 'Ein Somechin Al ha'Neis'?