For we have heard how Yahweh dried up the water of the Red Sea before you, when you came out of Egypt; and what you did to the two kings of the Amorites, who were beyond the Jordan, to Sihon and to Og, whom you utterly destroyed.
They said, When we take the city, you leave this scarlet rope out, and everyone who is within the house will be saved. If any of your family goes out into the streets, then they're taking their lives into their own hands, they'll be slain with the rest of the people. But in order that they might be spared and be saved, they've got to stay in the house ( Joshua 2:18-20 ).