I will be discussing the spiritual composition of man in this article based on my knowledge & experience, and therefore it is not set in stone or 100% correct; there might be a small chance that I’m wrong, but I don’t think so. That being said, let’s get to it.
Man is composed universally from 3 things: The spiritual, astral & the physical.
The spiritual is your soul, which is you, whom you are down to the core and will exist forever; it (so you) does not wither or fade and is free from negativity.
The astral is your astral body, which stores all emotions and feelings etc.; hate, anger, fear, sorrow, pleasure, pain are examples.
The physical is your physical body, which is your material body in which you’re able to thrive in the material world.
When you die in the traditional sense, as in moving on physically, your physical body moves on first of course. Then your astral body goes too. You will die twice, to make things clear. Your astral body will fade and go too, just as your physical one did and you will be whole and yourself to the fullest again. It is the astral body which enables clairvoyant faculties, e.g. Astral projection and magick overall. Baggage you might have mentally, e.g. neurosis, trauma and all related things are also residing in your astral body. When so, your astral body is corrupted and “filthy”. Hence some occult cleansing techniques you might have heard of, which absorb these negative energies and emotions. This also accounts for curses and black magick in the negative sense. Your astral body also needs nourishment in the same way your material one does; food, along with all other objects in the universe have astral energy attached to them. During rituals, food that is offered is not touched materially, but the astral energy is being absorbed by the spirits.
This is also why all, if not most, spiritual entities (with the exception of parasites) detest and hate the physical plane; it’s like living in the nicest neighborhood and then having to come down to the nastiest, grossest ghetto-ish place. This is how spirits see the material plane in a rough sense; it is beneath most of them (celestials & infernals) and the reason they come down to aid us is the same reason we do things for others: they can benefit from it. For them, it is about ascending via experience and knowledge by interacting with humans. This makes them stronger and more enlightened.