walk - are now setting out, namely, their ambassadors (Isa 30:4).
Egypt - See on Isa 19:1; Isa 20:1.
Pharaoh - the generic name of the kings of Egypt, as Caesar was at Rome. The word in Egyptian means “king” [Josephus, Antiquities, 8.6, 2]. Phra, “the sun,” was the hieroglyphic symbol and title of the king.
shadow - image from shelter against heat: protection (Psa 121:5, Psa 121:6).