Before the Promised Land, Moses gave instructions that the blessings and cursings of the covenant should be read aloud on Mt. Gerizim and Mt. Ebal :entered the
The same day Moses charged the people as follows: When you have crossed over the Jordan, these shall stand on for the blessing of the people: Simeon, Levi, Judah, Issachar, Joseph and Benjamin. And these shall stand on for the curse: Reuben, Gad, Asher, Zebulun, Dan and Naphtali. Then the Levites shall declare in a loud voice to all the Israelites … (Deut 27:11-14).
Then follow the blessings and the cursings, after each all the people shall say, “Amen”.
These instructions were carried out under the leadership of Joshua:
All Israel, alien as well as citizen, with their elders and officers and their judges, stood on opposite sides of the ark in front of the levitical priests who carried the of the LORD, half of them in front of Mount Gerizim and half of them in front of Mount Ebal, as Moses the servant of the LORD has commanded at the first, that they should bless the people of Israel. And afterward he read all the words of the law, blessings and cursings, according to all that is written in the book of the law. (Josh 8:33-34).
We may wonder how it was possible that the whole population of the Israelites, at least 600,000 adult men, could hear this reading of the law without a modern public-address system, and be able to respond with “Amen” to each of the blessings and curses.
An article on bibleplaces.com refers to an experiment conducted in the 19th century by J.W. McGarvey, during his tour of the Holy Land . He describes how these two mountains face each other with their slopes being about one mile apart, with the Biblical city of Shechem lying between them. On the side of both mountains there is a deep semicircular recess, which form two natural amphitheatres, where voices can carry for considerable distances. For his experiment, McGarvey stood between the two mountains, in the place where the Levities and the people of Israel would have stood. He said that there would have been enough space for 600,000 Israelites and their families. One of his two companions climbed halfway up Mt. Ebal , and another climbed halfway up Mt. Gerizim . Each evidently stood within the two natural amphitheatres, where they could each represent six tribes for the blessing and the curse.
The author read the blessings and the curses, and his two companions responded with, “Amen”, as Moses had instructed. The companion on Mt. Gerizim could hear the author clearly, and his response could also be heard clearly. The companion on Mt. Ebal could hear the voice of the author, but had difficulty distinguishing the words because of trees and terracing on the mountainside, which affected the acoustics. McGarvey suggested that if Joshua had a loud voice, he could have easily been heard by the whole the whole people of Israel , even without the Levites repeating his words.
This experiment shows that God chose the best place in the land to conduct this ceremony of renewal of the covenant, so all the congregation of Israel could hear the words of the Law clearly, and agree to them.
The natural amphitheatres do not work so effectively today because of recent building development, but still show clearly in photographs and aerial mapping.
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