Every birth in our world signifies a correction of the corporeal level of desires. Even if a person studied Kabblah in the past and reached a certain level, but not a final one, that person must be born as a baby, suffer, learn, and arrive at Kabbalah from the beginning. But the student will very quickly return to the level of the previous life and continue from there. There is never a repetition, only new corrections and additions to the previous life.
Rav Michael Laitman PhD
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