Комментарий к Дварим 27:1

שמר את כל המצוה — The word שמור is a frequentative present tense, gardant in old French, keeping in English

AND MOSES AND THE ELDERS OF ISRAEL COMMANDED THE PEOPLE, SAYING: KEEP ALL THE COMMANDMENT etc. The meaning thereof is that after Moses completed his words [to the people,] he ordered the elders also to join him and warn the people to keep all the commandments, for every nation follows the advice of its elders. It states which ‘I’ command you this day, not “we,” for the principal speech was that of Moses, while the elders merely proclaimed, saying to the people, “Hear, hearken, and observe.” Similarly, And Moses and the priests, the Levites spoke unto all Israel, etc.⁵⁵Further, Verse 9. means that the priests said to the people, Keep silence, and hear, O Israel,⁵⁵Further, Verse 9. and Moses said, This day thou art become a people.⁵⁵Further, Verse 9. But Rabbi Abraham ibn Ezra commented that the expression keep all the commandment⁵⁶In Verse 1 before us. refers to the commandment about the stones which he will mention further on.⁵⁷Verses 2-8. But this is not correct [since the verse states keep ‘all’ the commandment, it must refer to the commandments in general and not to one commandment in particular].

ויצא משה וזקני ישראל, G’d co-opted the elders seeing it was they who would stand at Mount Gerizim and Mount Eyval, and not Moses.