verses 9-10
The words of Moses which follow in Deu 27:9 and Deu 27:10, “Be silent, and hearken, O Israel; To-day thou hast become the people of the Lord thy God,” show the significance of the act enjoined; although primarily they simply summon the Israelites to listen attentively to the still further commands. When Israel renewed the covenant with the Lord, by solemnly setting up the law in Canaan, it became thereby the nation of God, and bound itself, at the same time, to hearken to the voice of the Lord and keep His commandments, as it had already done (cf. Deu 26:17-18).
verses 11-13
With the solemn erection of the stones with the law written upon them, Israel was to transfer to the land the blessing and curse of the law, as was already commanded in Deu 11:29; that is to say, according to the more minute explanation of the command which is given here, the people themselves were solemnly to give expression to the blessing and the curse: to the former upon Mount Gerizim, and to the latter upon Ebal. On the situation of these mountains, see at Deu 11:29. To this end six tribes were to station themselves upon the top or side of Gerizim, and six upon the top or side of Ebal. The blessing was to be uttered by the tribes of Simeon, Levi, Judah, Issachar, Joseph, and Benjamin, who sprang from the two wives of Jacob; and the curse by Reuben, with the two sons of Leah's maid Zilpah, and by Zebulun, with Dan and Naphtali, the sons of Rachel's maid Bilhah. It was natural that the utterance of the blessing should be assigned to the tribes which sprang from Jacob's proper wives, since the sons of the wives occupied a higher position than the sons of the maids - just as the blessing had pre-eminence over the curse. But in order to secure the division into two sixes, it was necessary that two of the eight sons of the wives should be associated with those who pronounced the curses. The choice fell upon Reuben, because he had forfeited his right of primogeniture by his incest (Gen 49:4), and upon Zebulun, as the youngest son of Leah. “They shall stand there upon the curse:” i.e., to pronounce the curse.
Verse 14
“And the Levites shall lift up and speak to all the men of Israel with a high (loud)voice:” i.e., they shall pronounce the different formularies of blessing and cursing, turning towards the tribes to whom these utterances apply; and all the men of Israel shall answer “Amen,” to take to themselves the blessing and the curse, as uttered by them; just as in the case of the priestly blessing in Num 5:22, and in connection with every oath, in which the person swearing took upon himself the oath that was pronounced, by replying
