God calls the people to look and be astounded because he is doing a work in their days that they would not believe if told. The verse highlights the unexpected nature of God’s action. This is in Habakkuk 1:5.
In Habakkuk 1:5–7 God answers the prophet by announcing a shocking intervention. The audience is told to look beyond their own situation to the wider world and be ready to be stunned, because God is already at work in their time in a way they will find unbelievable. These verses are God’s first direct response after Habakkuk’s opening complaint about violence and injustice among his own people (1:2–4). The response begins with a command to pay attention and to expect astonishment, then gives the reason: God is actively bringing about a major historical development.
Habakkuk 1:5–7 presents God’s first direct answer to the prophet’s complaint about unchecked violence and injustice (1:2–4). The text’s explicit claims are that God is already acting “in your days,” that the coming action will shock the audience, and that God identifies the instrument of this action as “the Chaldeans” (Babylon).
A careful answer keeps the immediate passage, the book's argument, and the whole-Bible storyline together, so the question is answered in context instead of as a detached idea.
Start with Habakkuk 1:5, then read the surrounding section so the answer stays connected to the passage's flow.
5"Look among the nations, watch, and wonder marvelously; for I am working a work in your days, which you will not believe though it is told you.