Take counsel together; literally, devise a device; i.e. form some plan, even the cleverest possible, against God's people, and the result will be utter failure. It shall not stand (comp. Isaiah 7:7).
For God is with us. In the Hebrew, ki 'immanu-El, "for with us (is) God" words declarative of the true meaning of the name which God had made a sign to his people (Isaiah 7:14). It was his being "with them" that could alone save them from their enemies.