Do you ever wonder why the majority of scientists deny God? There are two primary reasons.
The Presumed Infallibility of Science
Scientists are trained to think that all things can be answered by investigation and the scientific process. They trust their senses and the power of observation and the triumph of the intellect. They want clear evidence, certainty and proof. They want to discover the universe's laws and be able to form equations for every aspect of it. Though this isn't generally a bad thing, it presents a problem when we turn our thinking to the unfathomable and the infinite realm.
Humans are finite beings experiencing three dimensions and confined to a dimension of time. Just like we cannot truly imagine more than three dimensions, we cannot truly imagine something being infinite. When it comes to the philosophical topic of existence, scientists still want evidence. If there is a Creator, they think to themselves, we want to hear His voice and see His figure. They would like to observe Him using instruments, if possible. If God isn't definable using equations and laws, then He can't exist. There's just one big problem: logically, an infinite Being would not necessarily be observable or definable by finite creatures using their crude mathematical formulas. An infinite God wouldn't logically be small enough to fit into a definable, finite box. His existence would be unimaginable and could be transcendent above our universe and our limited observations. Yet, the normal scientist is too proud to admit his inability to wrap his finite mind around an infinite God.
The scientist is trained to look for a natural explanation for the origin of the universe and human existence. If he doesn't find good answers, he tirelessly presses on believing that answers will eventually turn up. Herein lies a problem. If some things are not answerable by finite beings using their finite observations, then those things will never be answered by science, but the scientist will persistently look for answers ad infinitum assuming blindly that an answer can be found. In such a case the scientist will vainly be looking for answers forever, finding only phantom mirages that eventually disappear upon closer scrutiny. He will be caught in an infinite loop of desperation. This is the state of the majority of God denying scientists; they try to explain existence apart from God and clutch the naturalistic explanations until they find them to be flawed.
God can never be believed until humility is found. The person who is trusting their own intellect has made Reason to be their god and savior. They are unwilling to admit that their god Reason can be fundamentally flawed because it is finite. If a mystery is presented, like, "Where did the universe come from?" they will simply say that is a problem that they are working on that will someday be solved by science. Mysteries are always just waiting to be solved by their savior Reason. Reason always triumphs in the end. What they fail to understand is that Reason doesn't have answers for the Infinite. If the universe has existed forever, then Reason fails to understand that. How could something not have a beginning? If God has always existed, then Reason fails as well. How could anything be uncreated?
The more honest or humble scientist will admit that science can't answer the imponderable question of existence of something as opposed to nothing. Infinite existence is not something that finite beings like us can appreciate, since we are finite and view everything through the lens of our own small existence. Yet, the typical agnostic scientist will raise the objection that God is no more reasonable than an uncreated universe that has always existed. But is that really true? For all the world, the universe seems clearly to have had a clear beginning! We call it the Big Bang. How did the universe exist forever? That idea is speculation and not hard science. So far, there is no good evidence that the universe has always existed, and the simplest answer is that the universe had a definitive beginning. If the universe appears to have had a beginning and yet has always existed, then we are crossing into the realm of the imponderable once again.
The universe is actually quite complex. Do we know that God would be more complex in His essence? Personhood is hard to define and to compare with a tangible universe. A Spirit like God is pure personality and does not require laws and equations. Raw personality is in some sense simple. We know by experience that imagination can be complex. Yet, we do not understand how imagination produces complexity. It is a mystery. The whole universe may be nothing more than an expression of God's infinite imagination. Cars are expressions of humans' imagination and ingenuity. In that sense, we cannot explain the existence of cars using mere physics and the laws of nature—i.e., why would cars specifically of necessity come into existence? Imagination does not seem to be predictable at any level or definable by science. If science cannot even explain why simple cars needed to exist or what will exist in a hundred years, then why would we think that science would be able to explain why the universe exists? Why would we think that an infinite Mind could not create a complex universe using His imagination such that no amount of observation and reason would be able to understand how it came into existence? Personhood is, and always has been, beyond the full understanding of science. Science doesn't have all the answers.
The only answer to existence is that there was something or someone who existed outside of time that is eternally unchanging and a constant. The Bible 'understood' this long ago. God is said to be Someone who "inhabits eternity" (Isaiah 57:15), who had no beginning (1 Chr. 16:36; Ps. 93:2), who is the self-existent "I Am Who I Am" (Ex. 3:14), who views time relatively (2 Peter 3:8), and who never changes (Mal. 3:6). He is the eternal Being who is unbound by time. This is scientifically and philosophically profound.
We need to add that the simplest answer is not always the correct answer. Occam's razor is only a rule of thumb. No one in their right mind really believes that the simplest answer is always correct. Generally, the simpler theories are better and more often correct, but not always. When you take the subjective experiences of people, the brilliant accuracy of the Bible, the complexity of existence, the unlikelihood of life coming into existence by itself, the spiritual nature of humans, the apparent finiteness of the universe, and the appearance of intelligent creation all throughout life on Earth into account, an infinite Creator seems like the simpler theory to where existence came from.
The Sinful Bias of Humans
The Bible says several times that man naturally has no interest in God (cf. Ps. 10:4; Rom. 1:21). More than that, man is said to naturally be at enmity with God (Rom. 8:7). Mankind is somewhat like a wife who has unreasonably divorced her husband just because she wanted more freedom. People are naturally aware of God's existence but they also are naturally disinterested in God. There is a natural bias against God according to the Bible. Herein lies a problem. There is a relationship problem, and no one really wants to acknowledge the true God.
Scientists are especially bad, since they become convinced that they have logical ways to get God off the hook, so to speak. They become too trustful of their own abilities to reason and explain things. Those who are smarter are better at reasoning themselves around inconvenient truth. Being smart is not always helpful. Many scientists have brilliantly—I say brilliantly!—found what look like ways to explain our existence apart from the power and wisdom of God. But they are self-deceived. They have unwittingly let their bias against God rule their thinking and poison their judgment. Their smart minds have fulfilled the desire of their hearts to run away from God, for you see the ultimate way to run from Him is to get your mind to think He doesn't exist. Once the mind has denied Him, the conscience can be easily suppressed and God's voice silenced. When someone doesn't want to believe something, it is common for them to resort to denialism.
Scientists generally reinforce one another's denialism. It is the blind leading the blind. In that, too, they find a sense of security apart from God. If "everyone" believes it, after all, how can it be wrong?
If the Bible is correct then you would expect there to be a lot of deniers of God's existence. The "wise of this world" are said to be especially blind to the truth (1 Cor. 1:26-28). That was written long before science really flourished. The wise of St. Paul's day were the Greeks and other philosophers, not scientists. Today, the wise are the scientists. The Bible accurately predicted that such people who are considered wise in the world would not often accept the truth of God. So, if you feel attacked as stupid for believing in the Bible, recognize that that is more confirmation of the Bible and humbly flee from the desire to have all the answers to existence . . . answers that others only proudly pretend to have.