Deuteronomy 27:1

And Moses with the elders of Israel commanded the people, saying, Keep all the commandments which I command you this day.

Keep all the commandments which I command you this day. This chapter should have commenced at Deuteronomy 26:16, for there Moses enters on the concluding part of the discourse which he pronounced on the plains of Moab; and having put the people in remembrance of the national covenant which had been mutually established between the Lord and Israel, by which He chose them for His people and they engaged to serve Him as their God, he proceeds to found on that solemn transaction a general but earnest exhortation to obedience.

Moses was surrounded, while giving his address, by the elders, or principal authorities in Israel, who by their presence, gestures, or audible declaration, not only approved of its strain, but united with him in enforcing fidelity to the divine service. Some further means, however, were thought necessary to promote the remembrance and observance of the divine laws.