Joshua 2:17 - Matthew Poole's English Annotations on the Holy Bible

The men said, or, had said; namely, before she let them down; it being very improbable, either that she would dismiss them before the condition was expressed and agreed; or that she would discourse with them, or they with her, about such secret and weighty things after they were let down, when others might overhear them; or that she should begin her discourse in her chamber, and not finish it till they were gone out of her house. Object. They spoke this after they were let down; for it follows, Joshua 2:18, this-thread which thou didst let us down by. Answ. Those words may be thus rendered, which thou dost let us down by, i.e. art about to do it; it being frequent for the pretertense to be used of a thing about to be done, by an enallage of tenses, as Joshua 10:15. Blameless of this thine oath, i.e. free from guilt or reproach if it be violated, namely, if the following condition be not observed.