Joseph Benson's Commentary of the Old and New Testaments - Deuteronomy 27:12
Deuteronomy 27:12. Upon mount Gerizim The original words may be rendered beside or near to mount Gerizim. There were in Canaan two mountains that lay near together, with a valley between, the one called Gerizim, the other Ebal. On the sides of these which faced each other, all the tribes were to be drawn up, six on a side, so that in the valley they came near each other, so near that the priests standing between them might be heard by them that were next them on both sides. Then one of... read more
Albert Barnes' Notes on the Whole Bible - Deuteronomy 27:11-26
Compare Joshua 8:32-35. The solemnity was apparently designed only for the single occasion on which it actually took place.Deuteronomy 27:12, Deuteronomy 27:13The tribes appointed to stand on Gerizim to bless the people all sprang from the two wives of Jacob, Leah and Rachel. All the four tribes which sprang from the handmaids Zilpah and Bilhah are located on Ebal. But in order, as it would seem, to effect an equal division, two tribes are added to the latter from the descendants of the wives,... read more