The living entity, who has received his present body because of his past fruitive activity, may end the results of his actions in this life, but this does not mean that he is liberated from bondage to material bodies. The living entity receives one type of body, and by performing actions with that body he creates another. Thus he transmigrates from one body to another, through repeated birth and death, because of his gross ignorance. — Srimad-Bhagavatam 7.7.47
“The death and birth is simply change of the body; the subtle body and the gross body.
Just like every night we die. The gross body remains inactive on the bed, and the subtle body takes me away. I dream, I go in the dreamland. I have gone to some friend, I am talking with somebody, I am working in a different way. That is our daily experience. This means that we have got two kinds of body. One body is this gross body, and the other body is subtle body, made of mind, intelligence, and ego. So foolish person, they do not see the subtle body, but the subtle body is there. Everyone will accept. I am working with my mind, intelligence and ego. Everyone knows. So although we cannot see the subtle body, it is there. So death means this gross body, this overcoat is left, and I am carried away by the subtle body, and I enter into another overcoat, or gross body. So practically this is called death. Because we have no vision of the subtle body, how the soul is being transferred or transmigrating from one gross body to another gross body, keeping the subtle body intact. And the subtle body is given up when one is liberated. And at that time he goes, when he is liberated, freed from this subtle body also, at that time he is promoted to the spiritual kingdom in spiritual body. Therefore while living in this gross body, we have to educate our subtle body in such a way that it becomes spiritualized completely.” – Srila Prabhupada