Stages of downward penetration of divine nature into a human individuality

From his twelfth year Zarathustra continued his development in the uniquely prepared astral body and ego of the Jesus of the line of Nathan. This is told in such an imposing way in the Gospel of Luke—the story of the twelve-year-old Jesus sitting in the temple among the Scribes, who were astounded at his words. How was this possible to the Jesus of the Nathan line? He was able to speak thus because the individuality of Zarathustra had entered him. Through that twelve-year-old boy who had been brought to Jerusalem by his parents, Zarathustra had not till then spoken. Hence the change in him was so great that his parents failed to recognize him as he sat among the scribes.