The post second temple Jews knew the Bible talked about a world ruled by God and were waiting for their savior to free them from their worldly overlord persecutors. The Old Testament gives hints of God’s world to come but doesn’t explain how salvation would arrive. Schooled in the philosophy of their captors, the Jewish leaders may have reasoned that a disembodied soul or spirit augmented the word of God. When pressed for scriptural support for their adopted belief, the Jews admit there are none. Using the teachings of men to support their faith they will defer to their own revered teachers. Unlike most modern professing Christians, the Jews do not believe they have to exclusively use the word of God to establish their beliefs. The Jews do not use their holy scriptures of the Old Testament to teach the immortal soul doctrine. Jewish scholars openly admit their belief in an immortal soul originated after they came out of Babylon, during the second temple period. Doing a basic Google search on, Jewish immortal soul history, will reveal the beliefs interesting origins, like this from the JewishEncyclopedia.com.
The belief that the soul continues its existence after the dissolution of the body is a matter of philosophical or theological speculation rather than of simple faith, and is accordingly nowhere expressly taught in Holy Scripture.
As a matter of fact, eternal life was ascribed exclusively to God and to celestial beings who “eat of the tree of life and live forever” (Gen. iii. 22, Hebr.), whereas man by being driven out of the Garden of Eden was deprived of the opportunity of eating the food of immortality…
Page from the First Edition of Immanuel ben Solomon’s “Meḥabberot,” Brescia, 1491.(In the Columbia University Library, New York.)
The belief in the immortality of the soul came to the Jews from contact with Greek thought and chiefly through the philosophy of Plato, its principal exponent, who was led to it through Orphic and Eleusinian mysteries in which Babylonian and Egyptian views were strangely blended, as the Semitic name “Minos” (comp. “Minotaurus”), and the Egyptian “Rhadamanthys” (“Ra of Ament,” “Ruler of Hades”; Naville, “La Litanie du Soleil,” 1875, p. 13) with others, sufficiently prove.
Content with believing what others say the Old Testament teaches, most Christians believe support for the immortal soul doctrine can be found there. Believing their doctrines are rooted in the word of God, many Christians do not prove if what they are being taught is God’s truth. Do you test your beliefs against the word of God?
Isaiah 9:16 International Children’s Bible
16 Those who lead the people lead them in the wrong direction. And those who follow them will be destroyed.