And he Moses, transfers Israel over it that they do not drown in it. It is this that is written: (Ex. 14:29) And the Children of Israel walked upon dry land, in-the-midst of the sea...
The first time, at the sea, salvation was in that substance the physical sea, whereas in the final redemption, it is all in the sea of Torah.
His staff, with which he splits the sea, it is the pen, because upon it is revealed ‘the arm of Y”Y’, of which it is stated: (Is. 53:1)... and the arm of Y”Y upon whom has it been revealed?