Isaiah 8:18

8:18 Look, I and the sons whom the Lord has given me are reminders and object lessons in Israel, sent from the Lord who commands armies, who lives on Mount Zion.

Isaiah 20:3

20:3 Later the Lord explained, “In the same way that my servant Isaiah has walked around in undergarments and barefoot for the past three years, as an object lesson and omen pertaining to Egypt and Cush,