Q. Did Isaiah really go around naked for three years?
It is possible this is meant, though it is not the only explanation. The entire context is:
20:1-4 In the year that Tartan came unto Ashdod, (when Sargon the king of Assyria sent him,) and fought against Ashdod, and took it; At the same time spake the Lord by Isaiah the son of Amoz, saying, Go and loose the sackcloth from off thy loins, and put off thy shoe from thy foot. And he did so, walking naked and barefoot. And the Lord said, Like as my servant Isaiah hath walked naked and barefoot three years for a sign and wonder upon Egypt and upon Ethiopia; So shall the king of Assyria lead away the Egyptians prisoners, and the Ethiopians captives, young and old, naked and barefoot, even with their buttocks uncovered, to the shame of Egypt.There is an extra explanatory phrase regarding the Egyptians – which was not referenced regarding Isaiah. That the text must explain that the prisoners would be taken away “with their buttocks uncovered” – which goes without saying if they were bare naked – suggests that Isaiah’s buttocks was not uncovered. What Isaiah pictured in type – naked and barefoot – would happen in a complete fulfillment for the Egyptians. They were not just “naked and barefoot” as was Isaiah in typology, but were “even with their buttocks uncovered.”
There are times in the Bible when “naked” means complete nudity (e.g. Genesis 2:25; Job 1:21). Sometimes being uncovered or naked does not mean complete nudity – more like dressed in only undergarments. When Michal described David as being uncovered he had on a linen ephod (See 2 Samuel 6:14-20). There are some other cases where naked may not mean naked to the skin with no clothes at all (I Samuel 19:24; John 21:7).
When we come to the definition of “naked,” in addition to “nude, without clothing” most English dictionaries gives one meaning of “naked” as something like “without adequate clothing” or “without proper clothing” or even “scantily clad”.
The preponderance of commentators do not think that Isaiah was completely nude (e.g. “What Isaiah was directed to do, therefore, was simply opposed to common custom, and not to moral decency,” Keil and Delitzsch). In contrast to Keil and Delitzsch, J. Alec Motyer writes, “The general use of the word (‘ārôm) suggests the former” (that is, that Isaiah was completely naked; The Prophecy of Isaiah, p. 171). There is also a question whether he went this way every day of the entire three years. The text seems to say that, but there is room to interpret it differently. For example, it may mean he went this way every time he was exercising his prophetic office during this period.
In the King James Bible ‘ārôm is used 16 times, always translated naked (Genesis 2:25; 1 Samuel 19:24; Job 1:21; Job 24:7; Job 24:10; Job 26:6; Isaiah 20:2-4; Isaiah 58:7; Hosea 2:3; Amos 2:16; Micah 1:8).
If we were weighing the evidence or taking a poll (that is, based on a majority of commentaries), “not completely nude” would definitely be the winner! But this is not the established way to understand the Bible. I think it is very likely that Isaiah was not completely nude, but am unable to establish the fact beyond doubt.