‘ Then she let them down by a rope through the window, for her house was on the town wall, and she dwelt upon the wall.'
The rope could have been fastened to some object in the room (they were no longer on the roof for there is a window) so that they could safely descend (compare 1 Samuel 19:12). She was probably used to doing this. A house on the wall was useful for a prostitute so that her clients could easily escape unseen if the need arose. Note the typical repetition common in ancient narratives.
In Joshua 2:14 Joshua 2:15 the activity is stated briefly and will be followed by an expansion in detail in the following verses. This was typical of early style. It causes some modern commentators difficulties because they overlook this difference in style,