Intriguingly, the ancient Epicureans identified the fear of death as the greatest obstacle to a life given over to temporal pleasures—further evidence of the universal sense of eternity (and expectation of judgment). To free themselves from the fear of death, they devised an atomistic anthropology in which we are nothing more than sentient material beings. Their only hope, in other words, was if death actually is the final end of us. This is more or less where many Americans are today, and one of the drivers behind the popular embrace of metaphysical naturalism in the secular West. If death is not our final end, then we must face the vanity of any life not lived for eternity.
No matter how vigorously one denies the afterlife, however, the sense that there is more than this present life stubbornly persists—so stubbornly that Immanuel Kant, who denied anyone could know such a thing, nevertheless conceded that we must at least believe in an afterlife in order to live rightly in this life.
Kant was partly right: reason alone “cannot” penetrate eternity to “find out what God has done from the beginning to the end” (Eccl. 3:11). And yet, the sense of eternity is stamped on our hearts just as firmly as are the awareness of God and the work of the law (Rom. 1:19–22; 2:14–16). Our consciences, desires, aspirations, and fears betray us.
Jesus did not move in a post-Enlightenment culture of secular agnostics as many of us do, but even Second Temple Judaism had its resurrection-denying Sadducees. Their denials, however, did not give Jesus any pause; He simply pointed out how basic the assumption of an afterlife (and future resurrection) is to the whole structure of biblical revelation and suggested that those who deny this “know neither the Scriptures nor the power of God” (Mark 12:18–27).