Isaiah, who is God’s faithful servant carrying out a symbolical action, had gone about partially naked and barefoot for three years. The symbolism represents the humiliation which the king of Assyria would carry out on all the Egyptians who would be naked and barefoot as they were being taken into captivity. Isaiah speaks of the king of Assyria as leading the Egyptians. Egypt and Cush are to be taken captive, and this captivity is for them to be led away. This was the current prisoner of war strategy. The Assyrians would take the captives back to Assyria. The whole purpose for these whose buttocks were exposed was a humiliation by God. The message of the symbolic act was very clear: it was absolutely fruitless to rely on Egypt for salvation.
Content retrieved from: https://www.sermonaudio.com/sermoninfo.asp?m=t&s=1027191740213712&fbclid=IwAR1QoisXrNOdFtnEWMYRb-hkbsTjK2OlNCrZyE94gOdgdojl5HtE0k2plSA.