Yahweh uses a question to emphasize that the idols have not told them these things. AT: "None of your idols has told this to you." (See: [[rc://en/ta/man/translate/figs-rquestion]])
# Yahweh's ally will accomplish his purpose against Babylon. He will carry out Yahweh's will against the Chaldeans
Here "ally" refers to Cyrus. Both of these sentences mean the same thing and are used for emphasis. (See: [[rc://en/ta/man/translate/figs-parallelism]])