זוהר שמות — דף פט ע”א

The Zohar recounts that Moses the faithful prophet departed from this world by the will of Atik Kadich and not by judgment, so his soul emerged and was concealed within Him, and the place of his burial was never known. The discussion concerns the secret of the additional Shabbat soul and its levels. The Zohar explains that Shabbat holiness begins at midnight on Friday, when souls leave the Garden of Eden to attach to the lower world. Rabbi Shimon comments on the verse concerning Shabbat observance and connects it to the spiritual preparation of the human being.