Kikiargos - Sorry, that was my attempt to explain without a lot of background experience/information.
We didn't actually leave it behind, we buried it because we are afraid of it.
We have to remember that having a personality with self awareness is a very new thing and has only existed for a short time. Before that we were like animals that lived only in the Life Will – what we usually call instincts. So the development of self awareness was an immense step, and left us very vulnerable, and still does.
Many people as their awareness reaches beyond what they feel is their normal self feel scared. Such resistances cause us to create awful dreams and fears as a means of avoiding our own huge inner world and its wonders. We feel that we will be swallowed up and we will die. It is important to say that when we meet the experience of powerlessness through becoming aware of the hugeness of your Life, which we are usually unaware if, it feels like something alien or it is attacking, and it is a shock.
When we begin to meet the Hugeness that we are, we often react to it in our dreams or in waking with fear or panic. So we dream of being attacked by aliens or frightening creatures; or being swallowed by a whale or something huge, a tsunami, or even possessed by evil entities. If we realise that they are things we have created through our own fear we will pass on.
This is all explained in Genesis - it is understandable of we change God for The huge experience that we lived in before we developed self awareness through language. See
And the eyes of them both were opened, and they knew that they were naked; and they sewed fig leaves together, and made themselves aprons. And they heard the voice of the LORD God walking in the garden in the cool of the day: and Adam and his wife hid themselves from the presence of the LORD God amongst the trees of the garden. And the LORD God called unto Adam, and said unto him, Where art thou?
And he said, I heard thy voice in the garden, and I was afraid, because I was naked; and I hid myself.
Naked because up till the start of self awareness they had been guided and protected by the immense world of the unconscious or what we call instincts. After that enormous step they had to depend on their own limited awareness. The fear was of being 'swallowed up' again into the enormous awareness of God/the unconscious. So the story of Jonah swallowed by a whale is about a human small awareness being lost for a while in the enormous ocean and whale. He was initiated into the huge and also maintained his ego.
See also
http://dreamhawk.com/interesting-people/animal-children/#Program And if you feel like exploring more see the whole series at the start of Dream Dictionary
http://dreamhawk.com/dream-dictionary/the-discovery-of-dreams/Tony