The notion of immortality is a selfish indulgence unrelated to the good of humanity. The concept of immortality originated well after the appearance of our species as an evolutionary entity, and so cannot have survival value which would lead to the reproductive success of those individuals who may have "carried" it. It is an unintended and unnecessary consequence of the evolution of the human brain complex enough to deal with the more concrete problems of survival, that also gives humans the ability to elaborate the intricacies of philosophy and theology, including the existence of the soul and our fate after death. In fact death, together with sex, was "invented" during the evolutionary process leading to human beings to continually wipe clean the genetic slate of a species and allow fresh genetic diversity in the form of new replacement individuals. Otherwise humans would have retained the "immortal" state of sexless, deathless amoebae and other less evolved organisms which reproduce by dividing themselves.
The quest for immortality, as out-of-touch with the rhythm of nature as it is, manages to solace the population sufficiently to blind humanity to the totally destructive effect it is having on the environment. The delusion of immortality submerges from view the destruction done in the name of humanity's territorial and religious imperatives.
"Immortality" in a Christian sense means the survival of man after his terrestrial death, for the purpose of eternal reward or punishment. Whoever only means by the term, the collective survival here on earth of his people for an indefinite length of time, distorts one of the fundamental notions of the Christian Faith and tampers with the very foundations of the religious concept of the universe, which requires a moral order. (Papal Encyclical, Mit Brennender Sorge, 14 March 1937).