In Exodus 14:1–31 we are told how the Lord caused the Israelites to walk through the Red Sea on dry land. When Pharaoh and his armies tried to follow them, the water closed in on them and they were destroyed. This took place more than forty years before the spies were sent into Jericho.
10 For we have heard how the LORD 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 Og, whom you devoted to destruction.