Chapter 51

51:9  Awake, awake, put on strength, O arm of the LORD; awake, as in the ancient days, in the generations of old. Art thou not it that hath cut Rahab, and wounded the dragon?

Art thou not

The ref. is to Egypt Isaiah 30:7 at the Exodus:

51:10  Art thou not it which hath dried the sea, the waters of the great deep; that hath made the depths of the sea a way for the ransomed to pass over?

ransomed

Heb. "goel,: Redemp. (Kinsman type). (See Scofield "Isaiah 59:20")