It means something. The whole autonomy rests with the individual conscience. But in a sweeping paradox, this same confession that seals the individual in his privacy with God draws him into an ancient communal bond. In this they resemble other national legislation, uniting many people under a legal system. But the national idea undergoes a startling extension at the outset, at Sinai.
Parallels break down.
The reader remembers the story. We Americans pay debts that dead congressmen contracted. We honor treaties that dead presidents signed, sometimes at the cost of our lives. We submit ourselves to a Constitution written by long-dead hands. It is the way of the world.