Stones for a Memorial 

Before the priests exited the riverbed, God had Joshua send the 12 men he had chosen (Joshua 3:12) over to the area around the ark to collect one large stone per man (Joshua 4:5). They also set up 12 stones in the midst of the river, probably as a visible disturbance of the current, if not actually extending above the surface, to commemorate the spot where the priests stood (verse 9).

The stones removed from the Jordan were taken to Gilgal, where they made camp (verses 19-20). Gilgal is about five miles from the river, but only about one mile from Jericho. The stones were to serve as a reminder of the miracle God performed that day (verses 21-24). Such monuments were often set up as "witnesses" of events (Genesis 31:45-52; Joshua 22:26-28; Joshua 24:26-27).

News of this great miracle quickly spread throughout the land, the inhabitants of which were gripped with terror. Indeed, imagine how the people of Jericho felt, with the Israelites camped only a mile away.