Higher than the question of our duration is the question of our deserving. Immortality will come to such as are fit for it, and he would be a great soul in future must be a great soul now.
A promise is a commitment to do something later, and a vow is a binding commitment to begin doing something now and to continue to do it for the duration of the vow. Some vows, or contracts, are for life; others are for limited periods of time.
This moment exhibits infinite space, but there is a space also wherein all moments are infinitely exhibited, and the everlasting duration of infinite space is another region and room of joys.