Among other reasons, the hope in a future life is motivated by the human wish to have a life which cannot be told.
Because a told event in actual life is one which is continually diminished by words and by the explanations they provide. Nonetheless, the life which does not deserve to be told belongs to someone who has not a definite identity.
Thus, when we want to underscore a great experience of life, we often say that it cannot be told. When it is spoken about, the words which are common to other similar experiences make it a common fact. Moreover, any singular experience is explained by appealing to perennial features of personality, ones that are common to other experiences, too.
On the other side, someone who wants to make from his life a story to be told does not hope in another eternal life. He tries to make eternal the present one.
The religious man is supported in his wish for an untold life by the religious myths and stories. It seems that the life which can be spoken is already lived in an exemplary way by gods and saints. The human beings could at most to imitate it in the present life.
From this reason, the religious life presupposes a slight personal identity; the eternal life is also conceived as a loss of a definite personal identity.