That walk to go down into Egypt, and have not asked at my mouth; to strengthen themselves in the strength of Pharaoh, and to trust in the shadow of Egypt!
That walk - that are now setting out namely, their ambassadors (Isaiah 30:4). To go down into Egypt - see note in the beginning of Isaiah 19:1-25; Isaiah 20:1-6.
Pharaoh - the general 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, who was considered as the representative on earth of the god RA, or the sun.
To trust in the shadow of Egypt - image from shelter against heat: protection (Psalms 121:5-6).