Lechem Mishneh: Souls & Spirits
On Shabbat all the souls and spirits descend and go out in pairs and there is no danger from Satan, as they protect each other. (Zohar, R”M, Eikev 273a) The Lechem Mishneh represents the joining of the souls of the husband and wife. It also represents the different levels of the Higher Soul joining together and connecting: The lower levels function with such awareness that they are able to lift even the Highest parts of the Soul and receive the full spiritual messages of the Higher parts of the Soul.
One should have intention to bring Shalom Bayit into his home when holding the two Challot together. He should also have in mind a prayer that all the levels of his Higher Soul should connect in Shleimut.