Why do people who do not believe in God try to live moral lives? Why do they follow the law of the country they live in? Why do they respect and love other people? This desire has no rhyme or reason, as nothing outside of themselves commands them to do so. There really is no point because the conclusion of their life is a dirt nap. Eternal black. If this is your end destination, why do anything at all? The end conclusion of an atheistic worldview is intense nihilism and the decay of morality.

Inevitable Nihilism
Think about it. You, a human being, a bag of flesh and water, made of stardust, with no inherent purpose, meaning, or worth, who evolved from primordial soup, exist on a big spinning rock of space dust, a mere speck in the greater universe. This one rock (out of many) can sustain life. The emotions that you feel mean nothing. They are biological processes happening in your brain. When you experience the emotion humans have deemed “love,” that is just how the chemicals interact in your brain and nothing more. Nothing on Earth or in the greater universe exists as an authority on what is moral and not moral, good or bad, right or wrong, etc.

You have no hope in life after death. You simply exist on this planet for however long it takes for your biological processes to wear down and quit working or for a freak accident to occur. Anything and everything you do during your lifetime will eventually be forgotten. You may even be famous or extremely influential, but thoughts of you and everything you have done will eventually fade.

In summary: your life means nothing, your death means nothing, and your actions mean nothing.

Thinking about life and existence this way would make even the sanest man mad. There would be no reason to get out of bed in the morning. If society fully embraced these ideals, there would be mass suicide, anarchy, and intense self-gratification.

If there is no reason to live and no hope after death, you could either:
Desire death, as living or being dead are both just as meaningless
or
Live every day for your pleasure

As society moves more and more away from God, these effects slowly take hold of America and the greater world. The mantra of “if it feels good, do it” seems to be embraced by most people today. Mass gluttony, greed, lust, and perversion are allowed and celebrated in America today. I would argue that the only solution to these problems is God.

The Christian has a purpose: To live to glorify God and to obey God’s commandments to the best of his ability. The Christian has hope after death: total freedom from sin and a union with God in heaven. A Christian worldview exemplifies a greater honor for mankind and Earth: God created the earth for man to dwell on. Even though man fell, God provided his son, Christ, as a sacrifice for sin, so that man may know God and be with him forever. God cares for man and for the earth.

Collapse of Morality
Without God, someone has no reason, ultimately, to believe in any cause or movement or to hold any belief. Without God, there is no ultimate good or evil. If humanity has no “ultimate lawgiver” or higher power delineating between right and wrong, then any view whatsoever that someone holds is valid. For example, if a man believes he should kill people, and someone else believes that killing is wrong, it doesn’t matter. Killing isn’t ultimately wrong; it’s just stardust bumping into stardust, so who’s to say that killing is bad or good?

In the words of the famous atheist Richard Dawkins “The universe we observe has precisely the properties we should expect if there is, at the bottom, no design, no purpose, no evil, no good, nothing but blind, pitiless indifference.” This is not how humanity has ever (or will ever) be organized in society or government, as it would lead to mass anarchy and lawlessness.

People can say that murder is ultimately wrong, and it would be true. Why? Because God, the creator of the universe, the ultimate good, agrees with them. He declared that murder was wrong when Cain slew Abel. He further declared it wrong when giving Moses the ten commandments. Only the Christian (at least, a religious person) has reason to appeal to ultimate morality and declare something wrong.

So, when someone appeals to beauty, emotion, and morality as though they were more than biological processes, or the products of our mind, they are inadvertently appealing to the religious worldview to do so.

When sharing your faith with a person who doesn’t believe in God, show them the obvious absurdity of their worldview and point them towards Christ so that they may repent and gain ultimate purpose and hope.