Isaiah 20 Judgment For Trusting In Man Alone.
Tartan was “probably not a name but a title designating a high officer in the Assyrian army,” and Ashdod was a Philistine city that “rebelled against Assyria at the encouragement of Shabako, the Nubian king. It fell in 711” (NGSB p. 1056).  As noted here by Isaiah, the Tartan was sent by Sargon the king of Assyria, with his forces, to fight against Ashdod and take it (v. 1). It was at this time that “the LORD spoke by Isaiah the son of Amoz, saying, ‘Go and remove the sackcloth from your body, and take your sandals off your feet.’ And he did so, walking naked and barefoot” (v. 2). Now, obviously no preacher would ever think of doing this today, but the prophets were often told to become visual aids to their audiences to back up the messages preached. For three years Isaiah was a living testimony, “a sign and a wonder,” of the judgment of the LORD against Egypt and Ethiopia, who would be taken captive by the king of Assyria-“young and old, naked and barefoot” (vv. 3-4).  This would show, to any who relied on these powers, that this would also be their outcome (vv. 5-6).
 “The biblical Ethiopia or ‘Cush’ is the remote region of southern Egypt and beyond, including Nubia, south of the fourth cataract of the Nile. The Nubian Shabako ruled over lower Egypt from 715 B.C. (twenty-fifth Dynasty). His administration tried to extend his influence northward into the delta region” (NGSB. p. 1053).
 “Earshaddon fulfilled this prophecy in 671 B.C.” The prophetic style of life (8:18; cf. Deut. 13:1, 2; Jer.32:20) pointed out the folly of relying pn Egypt, because Egypt, like any nation, was vulnerable” (NGSB p. 1056)