According to Josephus and others the Septuagint in his day composed only the five books of THE LAW of MOSES.
Do you have a quote on that?
It seems that if so, he was unaware of the writings at Qumran, who were wiped out during the fall of Jerusalem in 70 AD. Writings used by early Christians found at Qumran include Ps. 151 (found also in the Septuagint), Tobit, Sirach (found also at Masada in Hebrew) and the Letter of Jeremy (= Baruch 6). This pretty much blows the theory that the Septuagint was only formed AFTER Christianity came into being...
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