Passing the memory of the Jordan River crossing to future generations relies on a physical memorial. The stones set up after the crossing serve as a tangible prompt, ensuring that parents will tell their children the story of how they crossed the water.
Earlier moments in the narrative focused on the details of the miracle and the specific reasons it occurred. At this point, however, the focus shifts away from how the wonder happened and centers entirely on the event itself and the people who experienced it. While the waters of the river split by the merit of the Ark of the Covenant, the true emphasis is that this extraordinary event was performed first and foremost for the sake of the Israelites [מלבי״ם].