Constant repetition of a sakshatkara is required, as to make it a permanent possession. Instead of relying on a momentary glimpse of the view of something divine, one has to work one’s own self, till the self of the individual disappears in the self of the Universe. This is called Brahma Jnana– Brahman realisation.
Even this may be momentary. In order to become permanent, the sadhaka is advised to repeat it so that the impression (samskara) in the heart is far stronger and more serviceable. If one has really become identified with Brahman, death has disappeared.
Then, death has no meaning to a person, whose self has become the self of all, that is, who has lost his sense of separateness at once and forever.
"I draw to Me, My man from far off or even across the seven Seas to Shirdi, like a sparrow with a string fastened to its feet"-Shirdi Sai Baba, Indian Spiritual Guru-God 