Our adversaries said, They shall not know, &c. Their enemies resolved not to appear with an army before Jerusalem, but to march so secretly that the Jews should have no notice of their approach till they saw them in the city, armed and prepared to attack them suddenly, and put them to the sword.
Related Commentaries of Nehemiah 4:11
Nehemiah 4:11
11 And our adversaries said, They shall not know, neither see, till we come in the midst among them, and slay them, and cause the work to cease.