Yisro - Who Was Here First

Why does the Torah preface the revelation of the Ten Commandments with the statement that Hashem spoke 'all of these matters?' 

What is the depth of the concept of duality in the face of Hashem's absolute Unity? 

How do we understand what seems like darkness if Hashem is all 'light?' 

What is the depth of the idea of 'everything returning to the way it was at first?' 

How can the Jewish people be considered 'first' if there were many who preceded us? 

What is the true concept of 'first?' 

How does Hashem manifest as both a warrior and a gentle teacher?