What Scripture says
Scripture says moral knowledge is built into every person, not just believers:
- When people without the written law do what it requires, “they show that the work of the law is written on their hearts, while their conscience also bears witness” (Romans 2:15, ESV).
- Humans are made “in the image of God” (Genesis 1:27), which is why human life has worth (Genesis 9:6).
It also grounds goodness in God himself:
- “He has told you, O man, what is good; and what does the LORD require of you but to do justice, and to love kindness, and to walk humbly with your God?” (Micah 6:8).
- “You shall be holy, for I am holy” (Leviticus 11:44).
- “God is love” (1 John 4:8).
So the Bible explains two things at once: why everyone has moral convictions, and why those convictions point beyond us.
What the evidence says
Philosophy
The question isn’t whether atheists can be good
Of course they can, and many are kinder than many believers. The question is different: what makes moral claims objectively true? “Objective” means true regardless of what anyone thinks: torturing children for fun would be wrong even if a whole society approved of it.
The argument
- If God doesn’t exist, objective moral duties are hard to explain.
- Objective moral duties do seem to exist.
- So God is the best explanation of them.
Most people are as confident that some things are really wrong (genocide, child abuse, slavery) as they are of anything. When the Nuremberg trials judged Nazi leaders, the judges didn’t just say the Nazis broke German law; they said they did something wrong, whatever the law said.
C. S. Lewis made a related point: when we quarrel, we appeal to a standard both sides are expected to know (“That’s not fair!”). We don’t argue about mere preferences in the same way.
Why God helps
Theists argue that three features of morality fit God well:
- Objectivity. Moral facts are real and binding, not invented.
- Obligation. Moral duties feel like commands, and commands come from persons with authority.
- Human worth. Humans have dignity that doesn’t depend on usefulness. If we are made in God’s image, that makes sense.
The strongest atheist replies
Thoughtful atheists don’t usually say morality is just opinion. They offer several alternatives:
- Robust moral realism. Erik Wielenberg argues that basic moral facts are simply true, like the truths of logic or mathematics. They need no foundation, God or otherwise.
- Naturalist realism. Morality is about what helps conscious creatures flourish. Sam Harris argues science can, in principle, tell us what promotes well-being.
- Evolution and culture. Our moral sense evolved because cooperation helped our ancestors survive. Culture refines it.
- Anti-realism. Some atheists, such as J. L. Mackie, bite the bullet: there are no objective moral facts, though we act as if there are.
The theist’s responses
- To robust realism: it is strange for moral facts to exist as brute features of a purely physical universe. And it doesn’t explain why such facts should bind us, or why our minds should be able to know them.
- To naturalism: flourishing explains what is good for us, but not why we are obligated to promote others’ flourishing at our own cost.
- To evolution: evolution explains why we have moral feelings, but if those feelings were shaped only to help us survive, we have little reason to think they track moral truth. Philosophers call this an “evolutionary debunking” argument. Interestingly, some atheist philosophers, such as Sharon Street, use it to argue against moral realism itself.
- To anti-realism: it conflicts with our deepest convictions. Few people can live as though the Holocaust wasn’t really wrong.
Comparing the options
| View | Are moral facts real? | Where do they come from? |
|---|---|---|
| Theism | Yes | God’s good character and commands |
| Robust realism (atheist) | Yes | Nowhere; they are basic truths |
| Naturalism | Yes, in a sense | Facts about human well-being |
| Anti-realism | No | Feelings, culture, evolution |
Where they meet
Scripture’s claim that the moral law is written on the heart fits our experience: people across cultures share core moral convictions about fairness, honesty, care for the weak and loyalty. And grounding morality in a good, personal God explains why moral duties feel like commands from someone, not just useful habits.
What’s still open
- Whether godless moral realism is coherent is an active debate in academic philosophy, not a settled loss for either side.
- The Euthyphro dilemma (9.5) is the standard objection to grounding morality in God.
- Many people find the moral argument persuasive at an intuitive level even when the formal debate stays unresolved.
Bottom line
Without a moral lawgiver, objective moral duties are hard to ground, and that is a real point in favour of God. It is rated Debated because capable atheist philosophers offer alternatives that haven’t been decisively refuted.