Death: the inevitable mystery and our reaction to it provides the meat of the material of Gaudium et Spes 18
It is in the face of death that the riddle a human existence grows most acute. Not only is (a person) tormented by pain and by the advancing deterioration of (the) body, but even more so by a dread of perpetual extinction. (A person) rightly follows the intuition of (the) heart when he (or she) abhors and repudiates the utter ruin and total disappearance of his (or her) own person.
People also rightly follow their instinct of charity and justice by considering the death of others. That is why the passions are so aroused by life-and-death issues: war, abortion, capital punishment, and the like.
(People rebel) against death because (they bear in themselves) an eternal seed which cannot be reduced to sheer matter. All the endeavors of technology, though useful in the extreme, cannot calm … anxiety; for prolongation of biological life is unable to satisfy that desire for higher life which is inescapably lodged in (the human) breast.
So what does this say about the end of life? That the desire to prolong life is natural, understandable, and instinctive. But it is not the greatest desire for the Christian. The hope is that we long for some “higher life.”
Although the mystery of death utterly beggars the imagination, the Church has been taught by divine revelation and firmly teaches that (humankind) has been created by God for a blissful purpose beyond the reach of earthly misery.
That blissful purpose seems to be an original quality of the human person, not an exclusive reward for the believer.
In addition, that bodily death from which (people) would have been immune had (they) not sinned(Cf. Wis. 1:13; 2:23-24; Rom. 5:21; 6:23; Jas. 1:15) will be vanquished, according to the Christian faith, when (humanity) who was ruined by (its) own doing is restored to wholeness by an almighty and merciful Savior.
The completion of the plan of salvation, in other words.
For God has called (people) and still calls (them) so that with (their) entire being (they) might be joined to Him in an endless sharing of a divine life beyond all corruption. Christ won this victory when He rose to life, for by His death He freed (humankind) from death. Hence to every thoughtful (person) a solidly established faith provides the answer to … anxiety about what the future holds … . At the same time faith gives … the power to be united in Christ with … loved ones who have already been snatched away by death; faith arouses the hope that they have found true life with God.
If you are unfamiliar with Gaudium et Spes and operating on hearsay, you might be surprised by the philosophy and theology that dominates the reading of this document. I know I was the first time I read it. I had been led to believe that the peace and justice would be blaring from this constitution from word one. Instead, one can see a steady building up and a balance between affirmation of the human person with a serious acknowledgement of the reality of sin and evil. In this section, the reality of death as part of our fallen nature.