“to make known to your children.” This translation may be a little weak. The Hebrew is causative; make them know. It is a parent’s responsibility to teach their children about God. The assumption of Scripture is that children are curious and will ask questions, such as “What do these stones mean” (Josh. 4:21). At that time parents are to “make them know” the great deeds of Yahweh. Parents today often express that they want their children to “make up their own mind.” That will happen naturally. Eventually, every person makes up their own mind as they grow and mature. But it is the parent's responsibility before God to raise their young children in the nurture and admonition of the Lord. In reality, the children do not belong to the parent, they belong to God; the parents are simply the wards of the children until they mature, and so the parents are responsible to raise the children as the Heavenly Father would have them raised. To not teach children about God early on puts them at a serious disadvantage because they learn to live without thinking about God even though every breath of air they breathe is from God. Eternal life and eternal death are not things to take a chance on. Every parent should give their children the best chance to live forever. “...a child who is left to itself puts his mother to shame” (Prov. 29:15).
“dry ground.” The Hebrew is also used of the dry seabed of the Red Sea (cp. Exod. 14:22, 29).