A RATIONAL DEFENSE OF THE CHRISTIAN FAITH
INTRODUCTION
Christianity isn’t just a matter of blind belief or emotional comfort—it presents a worldview grounded in logic, evidence, and reason. In an age where skepticism often masquerades as intelligence, Christian apologetics offers a robust, thoughtful response. This presentation builds a rational case for the existence of God and the credibility of Christianity by drawing on cosmology, biology, philosophy, and science—while addressing the serious weaknesses in naturalistic explanations for life and the universe.
Ironically, as scientific discovery has progressed, the evidence for God’s existence has actually grown stronger rather than weaker. Dr. Stephen Meyer says, “The major developments in science in the past five decades have been running in a strongly theistic direction. Science, done right, points toward God” (quoted by Lee Strobel, The Case for a Creator, 2004, p. 77). Douglas Ell, an MIT graduate in math and physics who also holds a law degree, was a longtime skeptic about God. Yet no longer. He explains in his 2014 book Counting to God: A Personal Journey Through Science to Belief, “Each year brings new scientific evidence of wonder, facts for which there are essentially no explanations without God, [keeps occurring]....science and religion are converging” (pp. 13-14).
I. THE UNIVERSE HAD A BEGINNING -- AND A CAUSE
The Kalam Cosmological Argument offers a straightforward, logical foundation for the existence of God:
• Premise 1: Everything that begins to exist has a cause.
• Premise 2: The universe began to exist.
• Conclusion: Therefore, the universe has a cause.
This isn’t abstract speculation—it’s backed by science. The Big Bang theory, now mainstream in cosmology, indicates that the universe had a definite beginning [because it's expanding. If you run it backwards in time it reaches a starting point.]. Add to this the second law of thermodynamics: the universe is running out of usable energy, meaning it can't be eternal. Something outside space, time, and matter had to cause the universe. That "something" must be powerful, timeless, immaterial, and personal—matching the Christian concept of God.
The Contingency Argument adds depth. The universe is contingent—it didn’t have to exist. But things that are contingent require a reason for their existence. The only adequate explanation is a necessary being, one that exists by its own nature—again, pointing to God.
II. FINE-TUNING: THE UNIVERSE WAS DESIGNED FOR LIFE
A. Universal Laws
Zoom in on the structure of the universe, and a pattern emerges: incredibly precise fine-tuning. Scientists have found some 30 constants or laws of physics that govern the universe; like gravity, the cosmological constant, and the strong nuclear force are set at exact values that make life possible. Change any of them even slightly, and life couldn’t exist. The evidence points to “Someone” spending a lot of time tuning all of these laws so they would work in unison. This level of precision defies the explanation of random chance. The Anthropic Principle notes that the universe appears tailored for human life. But tailoring implies a tailor. The best explanation isn’t luck or a hypothetical multiverse—it’s intelligent design.
B. Our Home Planet: an Anomaly
In 1966, Carl Sagan hosted the famous TV documentary series Cosmos. He thought in order to have life you just needed two conditions—a right kind of star and a planet at the right distance. This conclusion proved to be totally off base.
Now, more than half a century later, scientists have come to the realization that more than 200 conditions have to be “just right” for life to exist and thrive. As author Eric Metaxas explains: “Today there are more than 200 known parameters necessary for a planet to support life—every single one of which must be perfectly met, or the whole thing falls apart. Without a massive planet like Jupiter nearby, whose gravity will draw away asteroids, a thousand times as many would hit Earth’s surface. The odds against life in the universe are simply astonishing” (“Science Increasingly Makes the Case for God,” The Wall Street Journal, Dec. 25, 2014).
III. PHILOSOPHY CONFIRMS WHAT SCIENCE SUGGESTS
A. The Moral Argument. Morality is real. Some things are always wrong—torturing children, genocide, rape. If morality is objective, it must be grounded in something beyond human opinion. But naturalism—belief that everything is just matter in motion—can’t account for moral law. At best, it explains moral feelings as evolutionary byproducts, but not binding moral truths. If objective morality exists, then a moral lawgiver exists. That’s God.
B. The Argument from Reason. If our thoughts are nothing more than chemical reactions shaped by survival, why should we trust them to tell us the truth? Evolution favors survival, not truth. Yet we rely on reason, logic, and abstract thought. These point beyond the physical brain to a rational soul—and ultimately to a rational Creator.
IV. EVOLUTION AND THE ORIGIN OF LIFE: SCIENTIFIC DOUBTS
Mainstream science often assumes that evolution and abiogenesis (life from non-life) explain everything without God. But the evidence doesn’t hold up as well as claimed.
A. Problems with Darwinian Evolution
• No mechanism for new information: Mutations can damage or rearrange DNA, but they don’t create the complex, functional information seen in life.
• Irreducible complexity: Some biological systems (e.g., bacterial flagellum) need all parts to work. Remove one, and the system fails—suggesting design, not gradual evolution.
• The Cambrian explosion: Dozens of complex animal forms appear suddenly in the fossil record, with no clear evolutionary ancestors. 70 % of all life-form types appeared suddenly, with no "missing links" preceding them. This evidence doesn't support evolution, but creation.
B. Abiogenesis: The Origin of Life
Science has never observed life arising from non-life. The leap from amino acids to functional, self-replicating life involves an astronomical level of complexity. British mathematician Fred Hoyle likened it to a tornado assembling a 747 from a junkyard. The odds are so low, they’re functionally zero. One of the discoverers of the DNA code, the atheist Francis Crick, concluded, “An honest man, armed with all the knowledge available to us now, could only state that in some sense, the origin of life appears at the moment to be almost a miracle, so many are the conditions which would have had to have been satisfied to get it going” (Life Itself: Its Origin and Nature, 1981, p. 88).
The human genome alone is a molecule with approximately 3 billion genetic letters, all precisely ordered to give instructions to the cell. From the most primitive cells to human beings, all have the same basic operating system of mind-boggling complexity, with codes, transmitters and receivers all working together. In addition, the origin of life puzzle has a “chicken-and-egg question”—which came first, the chicken or the egg? In this case, to get life to occur, you need both the complete genetic code and the proteins—the machine parts—that read the code and build new proteins. Without the code, you can’t build proteins. And without proteins, you can’t process the code. So how could both have arisen at the same time?
Biochemist Michael Denton describes the cell as similar to a a large city teeming with life and movement. If you magnified the simplest cell a billion times to be the size of London or New York, “we would then see...an object of unparalleled complexity and adaptive design....We would see around us, in every direction we looked, all sorts of robot-like machines. We would notice that the simplest of the functional components of the cell, the protein molecules, were astonishingly complex pieces of molecular machinery, each one consisting of about three thousand atoms arranged in highly organized 3-D spatial conformation.... despite all our accumulated knowledge of physics and chemistry, the task of designing one such molecular machine—that is one single functional protein molecule—would be completely beyond our capacity at present” (Evolution: A Theory in Crisis, 1986, p. 329).
V. LOGICAL PROOFS POINT TO A SUPREME BEING
A. The Ontological Argument proposes that if it’s possible that a maximally great being (God) exists, then He must exist in reality. While abstract, this argument forces a re-examination of how we define existence and possibility.
B. Meanwhile, Leibniz’s Principle of Sufficient Reason states that everything must have an explanation. The universe cannot explain itself. The best explanation is an eternal, necessary being—God.
CONCLUSION: Christianity Makes Sense of It All; Faith is Built on Reason
A. Christian faith is not a leap into the dark. It’s a step into the light. The origin and fine-tuning of the universe, the reality of moral law, the power of reason, and the impossibility of life from chance all point to a Creator. That Creator has revealed Himself—not just through nature and logic—but through Christ.
B. Robert Jastrow, a former NASA astronomer, humorously summarizes the point: "For the scientist who has lived by his faith in the power of reason, the story ends like a bad dream. He has scaled the mountains of ignorance; he is about to conquer the highest peak; as he pulls himself over the final rock, he is greeted by a band of theologians who have been sitting there for centuries."
[Some sections of this message contain segments lifted from Mario Seiglie’s article, “Seven Scientific Proofs of God.”]
