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.
Lecture on Srimad-Bhagavatam 1.2.8, New Vrindaban, 6 September, 1972