The following question was posted on my Facebook page several days ago:

I understand that the fine-tuning evidence for God’s existence is overwhelming. But how do we know that this God is a personal Being? I know it myself from the indwelling of the Holy Spirit, but how do I explain it to a skeptic?

I answer this question at length in my book The Creator and the Cosmos.¹ Here, I will provide a much briefer answer.

The experimental and observational evidence that the universe has a beginning in finite time establishes that the universe must have some kind of Beginner. Space-time theorems provide additional evidence that some kind of causal Agent beyond space and time created our universe of matter, energy, space, and time. I describe and document in much detail the experimental, observational, and theoretical evidence for this causal Agent in The Creator and the Cosmos.²

While this evidence for a cosmic causal Agent establishes deism (the existence of an uncaused Agent that created the universe but does not interfere directly with the created universe), it does not necessarily establish theism (the existence of a Supreme Being who not only creates the universe but also directly intervenes in shaping the created universe to achieve specific purposes and goals). Deists reject either that God is a personal Being or that the personal Being who created the universe intervenes in any way at any point in the history of the universe beyond the cosmic creation event. Theists, on the other hand, assert that God is a personal Being and that he has demonstrated his personality by directly intervening throughout cosmic history to achieve his personal goals and purposes for the universe.

Christians frequently cite the fine-tuning of the universe, Milky Way Galaxy, solar system, Earth, and Earth’s life to make possible the existence of human beings and human civilization as indisputable evidence that God is a personal Being. I explain why this evidence is so powerful in chapters 5, 6, and 14­–17 of The Creator and the Cosmos.³

In many cases, the level of fine-tuning of the universe and the laws of physics to make possible the existence of human beings, or their functional equivalent, measures far beyond the best examples of fine-tuning achieved by us humans. Some examples would be the needed fine-tuning of dark energy, dark matter, the force of gravity, and the force of electromagnetism. That this fine-tuning far exceeds our best human achievements implies that the causal Agent—who designed these features for the existence and benefit of human beings—is, at minimum, many orders of magnitude more intelligent, knowledgeable, inventive, creative, and powerful than we humans. Since intellect, knowledge, inventiveness, creativity, and power are attributes that only a personal being can possess, the causal Agent who created the universe must be a personal Being.

Fine-tuning evidence for the existence and benefit of human beings, and high-technology human civilization in particular, is not limited to the laws of physics and the gross features of the universe. This evidence for fine-tuning is ubiquitous. It exists on all size scales.

As I show in The Creator and the Cosmos, for humans to possibly exist in the universe, not only must the laws of physics and the universe as a whole be exquisitely designed, but also the cluster of galaxies, the galaxy, the host star, the planetary system, the host planet, and the host planet’s moon in which the humans reside.⁴ Furthermore, as I show in my book Improbable Planet, the physical, chemical, and biological history of the humans’ planet must also be exquisitely fine-tuned.⁵ The required fine-tuning extends all the way down in size scales to molecules, atoms, and fundamental particles.

No matter where in the realm of nature human investigators look, they will find overwhelming scientific evidence for the existence of God and for the personal attributes of God. A quick look at the four past editions of The Creator and the Cosmos will affirm that the more we learn about nature, the more evidence we gain for the existence of an all-knowing, all-powerful, all-loving personal God and for what Paul declared in Romans 1:20 (Christian Standard Bible),

For his [God’s] invisible attributes, that is, his eternal power and divine nature, have been clearly seen since the creation of the world, being understood through what he has made.