In Exodus 12:7, the upper door post signifies almost the same thing as the forehead with a man, i.e., the goods of love, here in the natural man. (Arcana Coelestia 7847)

Upper, in general, signifies the higher or highest degrees of the mind or spirit, and its particular significance depends on the accompanying words. (Conjugial Love 270[5];, Arcana Coelestia 4599)