The Midrash says that the meaning of “ascending and descending on it (bo)” (Gen. 28:12) is that Jacob’s image was engraved on the Throne of Glory, and the angels were comparing the ideal image of the heavenly Jacob with his image as it actually appeared below (Genesis Rabba 68:12).
This is a very demanding comparison: Does Jacobs actual appearance correspond to his ideal image, to what he is capable of being?
Likewise, the requirement of “You shall be holy, for I am holy” derives from the comparison of one’s heavenly image with one’s earthly image, as though to say: This is your source, this is your root, you originate from this ideal image; in light of this – how can you possibly sin?
That is why we say each morning: “My God, the soul that You gave me is pure.”
We start from above and continue below. It could be that during the day a person is occupied with all sorts of mundane things; nevertheless, he remembers that “the soul that You gave me is pure.”
The Talmud states that just as the beams of a person’s house testify against him, so do his own limbs and his own soul (Taanit 11a).
The Baal Shem Tov writes, “A person’s own soul will teach him,” meaning that one feels embarrassment when facing his own soul, his own heavenly image. In the same way, one is embarrassed in the face of the injunction, “You shall be holy unto Me.”
Rabbi Adin Steinsaltz