This question cannot be answered by a living person as he has not experienced death. It cannot be answered by a dead person since he cannot come back to narrate the experience. Only an enlightened being, a person who has gone through death consciously and come back anew, can exactly explain what happens during death.
I am going to reveal the mystery of death now. This may be surprising, even shocking to many of you. But this is the truth. Whether you believe it or not, accept it or not, this is what happens at the time of death. We do not just have one body. The physical body is just one of the seven bodies we have. It is the only gross body that can be felt and seen in space-time. However, we actually have seven layers or bodies or planes of existence. Since these layers have a subtle existence they cannot be seen or felt by the ordinary eye.
Each of the bodies holds a corresponding emotion. For example, the pranic body holds all the desires that arise in life. The mental body holds all the feelings of guilt experienced in life. The etheric body holds the experiences of mental pain felt in life.
When the spirit leaves the body it crosses all the seven body layers. The physical body dies. But, the remaining six bodies do not totally die. If you are holding a lot of desires in your life, all those unfulfilled desires are held in the pranic body. So even though the physical body dies, the pranic body does not die. When the life force leaves the pranic body, the being experiences tremendous suffering.
When you leave the physical body, your consciousness will be torn from the body and you will immediately fall into coma. According to doctors, coma is the automatic mechanism to make you not to feel the pain. It is automatic anesthesia. If the pain becomes too much, you can’t bear and you automatically fall into coma. When you move from the first body layer to the second body layer, all the unfulfilled desires, all the ways in which you wanted to live but did not live come up. When this happens, it is almost as if ten people are standing in a room kicking a football around. What will happen? Just like how the football is kicked from corner to corner, your consciousness will be kicked from all corners. In each corner, some desire will be standing and kicking it. At the time your consciousness is trying to leave the body, all your desires will be forcing you to re-enter the body so that you can enjoy them further and fulfill them.
On one side, the desires will be forcing you to enter the body again so that you can live and enjoy, while on the other side, the body will say, ‘No! I am tired. I can’t host you anymore, just leave!’ That is what causes the pulling and pushing at the time of death. The pulling and pushing is nothing but the fight between your desires and your body.
Somehow, you manage to move away from the pranic body, and enter next into the mental body. When you enter into the mental body all your guilt rises. All the guilt about the way you felt you should have lived your life but never lived, all the mistakes committed, all the regrets, everything comes up. Please understand, desire is about the future and guilt is about the past. But actually, both are one and the same. The way in which we want to live is desire, and the way in which we wanted to live but didn’t, is guilt. Guilt is nothing but reviewing our past decisions with updated intelligence. Like this, step by step, you move through different body layers.
The less the unfulfilled desires, the lighter is the pranic body and the easier it is to leave this body. Similarly, the less the guilt, the lighter is the mental body and the easier it is to leave this body.
One more thing, when the desires, guilt and pain are less intense, you not only have an easy death with less suffering but you also age gracefully. Ageing gracefully is what vanaprastha sannyas is all about. Being able to live in fulfillment in the latter part of life is the tremendous gift of vanaprastha sannyas.
All the guilt that we collect over our lives rises as we pass through the mental body. Then we come to the etheric body which is related to all our sufferings. All the suffering that we went through during our life is stored here. Like this, each and every body layer has got its own samskaras or stored memories. Actually, traveling through these bodies is what is spoken about as hell. There is no other separate place called hell. Hell and heaven are not geographical locations but merely psychological spaces.
The first four bodies are related to the physical body-mind system. They store all the engrams related to desires, guilt and pain experienced during that lifetime. The fifth body is experienced during deep sleep and when leaving the body. The sixth body is associated with happy memories and the seventh body is beyond sorrows and happiness, the ultimate consciousness.
Please understand, even attachment to happy memories brings us back into the cycle of birth and death. The desire to experience more and more similar incidents that are happy and joyful pulls us back and we take more births.
Understand, there is a big difference between bliss and happiness. Happiness comes from an external object or reason. For example, you feel happy when you get to eat your favorite candy. You feel that the candy is the cause of your happiness. But just think about it, if the candy was indeed the cause of you being happy, shouldn’t it give you happiness every time you eat it? Can you keep eating more and more of that candy? No! If you are forced to eat your favorite candy one after the other, what happens? You will get sick of it. You will start hating that candy and run at the sight of it!
Happiness is a temporary feeling created by the mind. Bliss, the seventh body, is the true reality. It is the causeless, unending happening inside you of spontaneous energy, joy and auspiciousness. It is like a fountain that continuously happens inside you for no reason.
Actually, the reason your favorite candy gives you happiness is that it acts as a trigger to put you into this space of bliss that is your true nature. But you mistake the happiness to be because of the candy, the external object. The happiness is because for those few moments, you come in touch with your inner bliss. The cleaner the bodies, the lighter they are and the easier it is for the life force to leave the body. Just like its peel comes off a ripe banana, the life force easily moves out of the body.
In the seven bodies, the first four bodies – physical, pranic, mental and etheric, collapse into the causal body every time you go to sleep. The darkness of the causal body is associated with the deep sleep state, which is what rejuvenates you every day. So till you cross the fifth body, this ‘death’ happens every day. This is what happens when you fall into your daily sleep.
When the departing spirit moves beyond the fifth layer of causal body into the sixth layer, which is the cosmic body the process of death is complete. If the life force does not have to take another body to fulfill its remaining desires it then enters the seventh layer of nirvanic body, which is enlightenment. If the life force has to come back assuming another body to fulfill its desires, it is death.
source: Living Enlightenment