Iyov II
“The Arizal concludes by saying that this is why Satan considered Job a fair exchange for the Jewish people, and why it was not unjust that G-d offered him as “ransom” for Israel. Before his trial, he was the as yet unrectified Terah, the source of the evil of idolatry that the Jewish people were in the process of uprooting. But whereas the line of Abraham was on the way to receive the Torah, i.e., to replace idolatry with its opposite, the true spiritual path, Job’s task and trial was merely to renounce idolatry and remain true to G-d throughout his test. Since he thus represented the hope and perfection of the rest of humanity, Satan was satisfied to vex him instead of the Jewish people. Unwittingly, he thereby enabled Job, and by extension, all humanity, to reach perfection.”
