The emphatic 'I, behold, I' stresses that this is entirely God's initiative — He is doing this. And the covenant extends to all descendants — future generations are included in what God is promising today.
Memory phrase: God's promise covers all generations.
Talk about it: What does it mean that the covenant is also for the children who have not been born yet?
Prayer: God, thank You that Your promises reach to my children and to their children.