Jamieson, Fausset and Brown on Deuteronomy 5:5

5. I stood between the Lord and you at that time--as the messenger and interpreter of thy heavenly King, bringing near two objects formerly removed from each other at a vast distance, namely, God and the people (Ga 3:19). In this character Moses was a type of Christ, who is the only mediator between God and men (1Ti 2:5), the Mediator of a better covenant (He 8:6; 9:15; 12:24).

to show you the word of the Lord--not the ten commandments--for they were proclaimed directly by the Divine Speaker Himself, but the statutes and judgments which are repeated in the subsequent portion of this book.