Man's Days Are Numbered

The heart beats earlier than expected, but seems to have a limit.

Moses lamented that compared to God’s eternality and immutability, our mortal lives are but a breath. The classic King James English puts it, “The days of our years are threescore years and ten; and if by reason of strength they be fourscore years, yet is their strength labour and sorrow; for it is soon cut off, and we fly away” (Psalm 90:10).

Recent science news suggests that our days are numbered. Our hearts begin to beat sooner than scientists had thought, Medical Xpress says, but quickly notes that humans get a normal limit of about 3 billion heartbeats – some more, some less. To find out about the onset of heartbeats, the British Heart Association studied mouse embryos. Extrapolating their measurements to human gestation, they think the human heart begins beating just 16 days after conception. “Previously, it was thought that the heart started to contract a stage later, when the heart appears as a linear tube,” the article says, so this is a dramatic finding. The heart is the first organ to form during pregnancy. It will beat for many years—but not forever.

But “When, and why, must we die?” PhysOrg wonders. The author of this article gives a common evolutionary explanation:

We must die eventually, he suggests, because humans have a body design that evolved to hang in there long enough for us to live long enough to reproduce, ensuring the survival of the species. Once we’ve accomplished that, he suggests, nature has been spectacularly indifferent to parts that wear out, electrical currents that short-circuit, and cells that act on bad information and replicate like crazy.

Our bodies, in short, did not evolve to live into extreme old age.

Three researchers from Albert Einstein University in New York disagree. Writing in Nature, they say that whatever causes death, it’s not natural selection tossing human bodies out after they’ve reproduced (clearly, many people live long after their childbearing years). Instead, there appears to be a built-in limit to human lifespan.

What could be the biological causes of this limit to human lifespan? The idea that ageing is a purposeful, programmed series of events that evolved under the direct force of natural selection to cause death has now been all but discredited. Instead, what appears to be a ‘natural limit’ is an inadvertent byproduct of fixed genetic programs for early life events, such as development, growth and reproduction. Limits to the duration of life could well be determined by a set of species-specific, longevity-assurance systems encoded in the genome that counteract these inadvertent byproducts, which are likely to include inherent imperfections in transferring genetic information into cellular function. To further extend human lifespan beyond the limits set by these longevity-assurance systems would require interventions beyond improving health span, some of which are currently under investigation. Although there is no scientific reason why such efforts could not be successful, the possibility is essentially constrained by the myriad of genetic variants that collectively determine species-specific lifespan.

How far can we extend human life? There have been efforts at some labs to extend life. And why not? Except for the need to work out a few kinks politically, like how to keep Social Security going for a few more decades without going broke, why can’t science find ways to increase our length and quality of life? Despite better health, sanitation and safety, the average age of the oldest person has not been increasing for several decades, they say. “Our results strongly suggest that the maximum lifespan of humans is fixed and subject to natural constraints.”

Death is not natural. It intruded into the “very good” creation as a result of sin. Death is the righteous sentence of our loving and holy God who warned our first parents that they day they ate of the tree He commanded them not to eat from, they would surely die. They ate; they died. They were dead the moment they ate, just like a leaf pulled from the tree is dead, though it be green for hours or days. Adam and Eve’s bodies eventually caught up with their spiritual separation from God.

Through their disobedience, they fell into an ungodly state unfit for God’s presence, and were banished from the perfect garden, taking all their corrupted human seed with them. “And so death passed among all men, for that all have sinned,” Paul explained in his treatise about sin and death in Romans 5. With their fall, the creation fell. Pain, disease, and suffering intruded into a world where Satan would have temporary dominion as the “god of this world.”

The Biblical worldview sees death as an enemy that will be conquered in the new heavens and new earth. In this life, “It is appointed unto man once to die, and after that the judgment” (Hebrews 9:27). But God did not leave man without hope. He set up a process of mediation, first through human priests, to intercede between fallen man and his holy Creator. The law of Moses taught through graphic and costly visuals that another’s death, the death of a sacrificial animal, could atone for the guilt of sin. And so the temple sacrifices continued day after day. But it is impossible for the blood of an animal to forgive sin. These were tutors to lead man to the ultimate High Priest, God the Son in human flesh, who would give His life as the perfect once-for-all sacrifice. Salvation has always been by faith in God’s promise.

Now that Christ has died and risen in real time-and-space history, those who trust in His substitutionary atonement can accurately say they have “died with him” in a legal sense (Colossians 2). Their sins have been nailed to the cross. And as Jesus rose in the power of the Holy Spirit, those who trust in Him will rise also. Except for those who are alive and remain at His second coming, we must each die first physically, then be resurrected (I Thessalonians 4). In I Corinthians 15 (worth reading in full on this subject), Paul says, “The last enemy that shall be destroyed is death” (v. 26). The hope of resurrection like that of Christ empowers us to work joyfully, knowing that our labor for the Lord is not in vain (v. 58).

In a sense, the sentence of death was an act of God’s mercy. If we lived forever in a fallen state, there could be no redemption. “The wages of sin is death” (Romans 6:23). That wage must be paid, because the Judge of the universe is perfectly just. But the verse continues, “the gift of God is eternal life in Jesus Christ our Lord.” We will each get the death we have earned by our sin—eternal separation from God—or we can accept Christ’s death on our behalf, and receive His free gift of eternal life.

This fallen world rejects its Creator. That’s why so many smart people accept Darwinian evolution: it becomes their designer substitute, their idol, that lets them feel like they can sin without consequences. But none of them will escape death that is appointed to them, and after that, the judgment. John writes of the Word who was God who became flesh: “He was in the world, and the world was made by him, and the world knew him not. He came unto his own, and his own received him not. But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name” (John 1:10-12). You could receive Him today.

Exercise: Study these historical realities and doctrines in the links above. Look especially at Genesis 1-3, Paul’s epistle to the Romans, the epistle to the Hebrews, and the Gospel of John. At the BibleGateway.com, you can switch to a more modern translation like the English Standard Version (ESV) if you prefer. But don’t just take our word for it. Know these truths from the Word of God itself.