“Then they shall be dismayed and ashamed because of Cush their hope and of Egypt their boast” (v5). God used Isaiah as a living prophecy to warn people about the destruction to come. Isaiah walked around naked and barefoot (v2) for three years to show what was going to happen: the Assyrian empire would crush the Cushites and the Egyptians and lead many into exile. Those who had leaned on these nations for support and protection against Assyria would see that they too were vulnerable.
“Behold, this is what has happened to those in whom we hoped” (v6). If we put our trust in anything but God – leaders, work, relationships, ourselves – we will be disappointed. God alone will never fail us.