The Muslim answer is that objective morality is grounded in Allah: His perfect knowledge, justice, wisdom, and command. That answer is not a shortcut past moral reasoning; it explains why moral truths are real, binding, and finally accountable.
The question at its strongest
The challenge is usually put like this: if there is no God, morality may still exist as feelings, social agreements, evolutionary instincts, or practical rules for human cooperation. But why would any of that be objectively binding? Why would torturing an innocent child be truly wrong, even if a society approved it, or if someone personally enjoyed it?
That is the strongest form of the argument. It does not say atheists cannot be moral. Many are kind, principled people. Nor does it say believers always behave morally. The point is deeper: what makes moral claims true and authoritative rather than merely preferred?
What Islam means by a moral source
In Islam, morality is not an accident of biology or a vote of the majority. It comes from the Creator, who made human beings, knows their nature, and will judge them with perfect justice. Allah is not imagined as a powerful ruler inventing arbitrary rules. He is al-Hakim, the All-Wise, and al-Adl, the Just. His commands express perfect wisdom, not mood or need.
Indeed, Allah commands justice, excellence, and giving to relatives and forbids immorality, wrongdoing, and oppression. He admonishes you so that perhaps you will be reminded.
Quran 16:90
This gives morality three things that mere preference cannot give: reality, obligation, and accountability. Reality: good and evil are not just names we attach to likes and dislikes. Obligation: I must do what is right even when it costs me. Accountability: no injustice disappears simply because the victim is weak or the criminal escapes court.
O you who believe, stand firmly for justice, as witnesses for Allah, even if it be against yourselves or parents and relatives.
Quran 4:135
Reason, fitrah, and revelation
Islam does not teach that people know nothing about right and wrong unless a verse is quoted to them. Human beings have fitrah, a created moral nature, and reason can recognize many moral truths. People can see that gratitude is noble, betrayal is ugly, and cruelty to the innocent is evil.
By the soul and the One who proportioned it, and inspired it with its wickedness and its righteousness.
Quran 91:7-8
The Prophet (PBUH) also pointed to the moral conscience, while not making it independent of revelation:
Righteousness is good character, and sin is what wavers in your soul and you dislike that people should come to know of it.
Sahih Muslim
Classical scholars therefore distinguished between recognizing moral value and being held finally accountable by divine command. Reason and conscience are real, but they are not infallible. They can be clouded by desire, culture, fear, and pride. Revelation corrects, clarifies, and completes them.
What the argument proves, and what it does not
The moral argument establishes a serious point: if objective moral duties truly exist, then a personal, wise, just Creator explains them far better than blind matter, social fashion, or survival instinct. Evolution may explain why we have certain moral feelings; it does not by itself explain why we ought to obey them when they conflict with self-interest.
A secular moral realist may reply that moral truths are simply brute facts, needing no further grounding. That is the strongest non-theistic reply. But it leaves moral obligation strangely floating: real, yet impersonal; binding, yet without a commander; violated, yet with no final justice.
Still, this argument alone does not prove every detail of Islam. It establishes that objective morality points powerfully toward God. To show Islam specifically, one must also examine revelation, prophethood, the Quran, and the life of Prophet Muhammad (PBUH).
So the Muslim answer is plain: our source for objective morality is Allah, known through fitrah, reason, and revelation. This gives moral life both its seriousness and its hope.