Natural law does not depend on a historical narrative such as the stories told in the Bible since it can be known to any man. The Bible cannot give us knowledge of (Deus sive Natura) because that knowledge comes from experience with the everyday world.
Still reading the Bible may be useful by giving the reader knowledge of men's customs and circumstances that determine their actions so that we may learn how to act among them.
Natural law requires no ceremonies. In Spinoza's words, The natural light of reason does not demand anything which it is itself unable to supply. Those things that authorities may call good and demand be preformed do not arise from the sound mind nor the intellect.