I disagree. There is no reason Isaiah can't be studied using the same methods one would use to study the Iliad. But we need to understand that the conclusions of any such analysis are speculative, and that they don't change the meaning or significance of the scripture.
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If one could look at the chronology and any corresponds between Biblical times of that day! We might see some of the same situation being repeating today!
How the world related to those of the religious community.
Sometimes when reading scriptures one focus on the immediate region and not on the climate of the whole nation that effects each other on some level.