Hi Natasha,
 

To answer your question is very easy, but to comprehend the real big picture of life, is a little more complicated. If you want to know, How our World, your human Soul and Man is really Created, step by step and in detail, just bear with me.
 

How can a Soul remember everything from a human life experience?
 

The reincarnation process (“The Rebirth”) works in short as follows;
 

A Godly Soul descends from Heaven, with the desire to reincarnate unto a human vessel, to experience temporary to be a human being.
 

Literally to become partly a human Soul, experiencing a Man’s life.
The Godly Soul “split” figuratively a part of consciousness without the Godly Soul’s own thoughts, with all memories of previous lives and personality. What becomes the cleared of memory Consciousness and Awareness of Man. What is called a human Soul. The Godly Soul connects this human Soul with a human vessel, a baby before birth.

During a human life, Man is formulating thoughts, memory and personality, it fills the human Soul with these thoughts, memories and personality. Thoughts are energy patterns, and these energy patterns are created in the energy field of human Soul. A human Soul observes and is aware of a human life. A human life is created so perfectly by God, that a human Soul believes it is experiencing a real human physical reality. Not realizing, that Everything is expressed Energy.

When the human vessel dies in a seemingly human life reality, then your Awareness and Consciousness shall awaken after about 3 days in your human Soul. For clear-cut reasons. The human Soul awakens in another In-between dimension (Between Earth and Heaven). In your Real, for most people unknown, In-between life. As a human Soul, between being a Man on Earth and a Godly Soul from Heaven.
 

Real dying is the same as just falling asleep, and awaken very slowly in the In-between dimension. Where slowly your thoughts, memories of this previous human life and personality shall be triggered in a slow pace to awaken, and you shall be able to remember your past human life. To make Real dying a very tranquil process, without panic, fears or worries. Perfect, Kind and Loving created by God. So, there is no need for fear of dying. What means Life after Death as a human Soul exist. What almost all people do Not know is, that your Soul’s life is much more Real, than your human life Reality feels for you.

After the human Soul, as thoughts, memories and personality has learned from All Lessons of Life and Really purified it’s Soul on Earth. Into Only Harmonious, Loving and Positive thoughts, then it has raised it’s energetic frequency of human Soul unto a high level. What is called to lift a human Soul. Only then, the human Soul is Ready, to merge back into the Always and Only Loving and Harmonious thoughts, memories and personality of a Godly Soul. Because, high energetic frequencies of the human Soul and Godly Soul matches and allows merging. What means the thoughts, memories and personality of the human Soul shall be merged into the previous Godly Soul. Literally you become yourself, as a Loving and Harmonious Godly Soul again.

When you are your Godly Soul again, then you shall instantly be able to remember all past lives as Man and Soul you have experienced. 
 

As a Godly Soul, you shall Know EVERY SMALL DETAIL of your past human life experience. Even what happens exactly at time of your passing over (=death) of your human vessel. Conscious you were sleeping, but subconscious you were still Observing your death with your human Soul. All explainable into the tiniest details. To be able to store Everything that happens during your human life experience in high detail, even things you cannot remember as Man, you still know as a Godly Soul. Your human Soul becomes after merging again, your Godly Soul. And you are able instantly to remember everything of your complete Godly Soul’s life and shall leave the In-between dimension and ascend back to a higher frequency dimension called Heaven. Heaven is God’s Loving and Harmonious Consciousness.

This complete process, what happens exactly after death is known and is explained, step by step in the Book of Life Age of Harmony 2025-4185, and in the other answers I have written for All on Quora.

After every reincarnation the Godly Soul shall return first to Heaven. Before the Godly Soul can decide with free will to have another reincarnation.
 

To understand the Mysteries of God’s High Creation of Life is Not difficult, it is just very different, than Man and even Prophets have assumed it to be.
 

It is what it is, nothing more and nothing less.

Life is all about thoughts and choices.
Choose well.

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