For example, take the apple. A simple symbol. Strip away everything else and you are left with food grown from a seed. The cultural layer is dependent upon the culture being studied. Obviously a Western interpretation would differ from an Eastern and etc.
Culture also includes a time reference.
Let's take the apple once again. Now to show the cultural difference, look at the apple in the modern computerized technological world. The third layer to symbols is the personal reaction. One who is allergic to apples would have spent their whole life avoiding the fruit and this would color their reaction to the symbol. The mixture of personal and cultural could be that one develops an antipathy to the Christian religion and somehow that religion becomes internally symbolized by the fall from grace episode.