Isaiah 51:9

"Awake, awake, put on strength, O arm of Jehovah; awake, as in the days of old, the generations of anclent times. Is it not thou that didst cut Rahab in pieces, that didst pierce the monster? Is it not thou that driest up the sea, the waters of the great deep; that madest the depth of the sea a way for the redeemed to pass over? And the ransomed of Jehovah shall return, and come with singing unto Zion; and everlasting joy shall be upon their heads: they shall obtain gladness and joy; and sorrow and sighing shall flee away."

Kelley believed that here the prophet Isaiah himself is the speaker, and that he was pleading for God to intervene upon behalf of Israel as in the days of previous generations; but other speakers have been suggested, such as "Zion, angels, the prophet Isaiah, and the Son (the Ideal Servant) pleading with the Father, and that it is Jehovah addressing himself!"[13] One may take his choice; we fail to see that it makes a lot of difference.

"That didst cut Rahab in pieces ..." (Isaiah 51:9). The name Rahab is here a poetic name of Egypt, just as Gotham is the poetic name of New York City. The name's connection with some ancient Babylonian myth is of no significance whatever and certainly does not signify any Biblical endorsement of ancient mythology. Rahab is used for Egypt in Psalms 87:4, and also in Psalms 89:10. Some versions render the Hebrew word as Dragon; but this also means Egypt (Psalms 74:13).

God in this passage is referred to as the one who dried up the waters of the sea and made a way for the redeemed to cross over. This, of course, is a reference to the Exodus on dry land through the Red Sea (More properly, the End Sea); see my article on this in Vol. 2 (Exodus) of the Pentateuchal Series of the Commentaries, pp. 177-179. This indicates that in some way, the coming out of Babylon by the righteous remnant would be considered as "a new exodus."[14] There are overtones here also that reach far beyond the return of captives from Babylon. The quotation here in Isaiah 51:11 from Isaiah 35:10 is proof enough that a tremendous deliverance is promised.

As Jamieson noted:

"As surely as God redeemed Israel out of Egypt, He will redeem them from Babylon, both from the literal Babylon in the age following Isaiah, and from the mystical Babylon revealed in Revelation 18:20,21, which is the last enemy of Israel and the Church, from which they have long suffered, but from which they are to be gloriously delivered."[15]