6 We will use these stones to build a memorial. In the future your children will ask you, 'What do these stones mean?' 7 Then you can tell them, 'They remind us that the Jordan River stopped flowing when the Ark of the Lord 's Covenant went across.' These stones will stand as a memorial among the people of Israel forever." 8 So the men did as Joshua had commanded them. They took twelve stones from the middle of the Jordan River, one for each tribe, just as the Lord had told Joshua. They carried them to the place where they camped for the night and constructed the memorial there.
Matthew Henry's Commentary on Joshua 4:6-8
Commentary on Joshua 4:1-9
(Read Joshua 4:1-9)
The works of the Lord are so worthy of rememberance, and the heart of man is so prone to forget them, that various methods are needful to refresh our memories, for the glory of God, our advantage, and that of our children. God gave orders for preparing this memorial.