This is the weekly Q & A blog post by our Research Professor in Philosophy, Dr. William Lane Craig.


Dear Dr. Craig,

My question is on objective morality. I lead a Christian life group of 11th and 12th graders, where I often use apologetics to show them that belief in God, specifically Christianity, is not only the true religion, but also the best explanation for the origin of the universe.

I firmly believe that equipping teenagers in this particular stage of life is essential to firmly ground their beliefs and also to explain their reasons for holding such beliefs as they prepare for university and the work force.

With regard to objective moral value though, I find myself wrestling with a problem. I do agree that without God there cannot be moral objectivity, but where do we get the rules for morality?

If one is to refer to the 10 Commandments as the source, all is well and good except for the fact that there was no moral law from the time from Adam to Moses. I even recall reading that 400 years passed between Abraham and the giving of the 10 Commandments.

so this raises the question of how did people know moral obligations prior to Mt. Sinai? Scripture clearly teaches that moral obligations existed prior to the 10 Commandments, such as Joseph refusing to sleep with Pottifer's wife, claiming that doing so 'is a sin against her husband and against God.'

This is not just an internal problem within Christianity, but I have heard this objection from atheists and agnostics too. The only defense I have come up with to date is to quote the scripture that 'God has written his laws on our hearts,' but that gets into Christian theology which I find is too far of a mental stretch for some by simply showing how theism is necessary for moral obligations.

How can Christians answer this moral obligation question for people living prior to the time of Moses?

Thank you for all of your work and ministry. It is vital not only for my own personal faith, but also the faith of the students I equip.



United States

Dr. William Lane Craig’s Response

Dr. William Lane CraigThank you, Tarick, for your commitment to these high school students to equip them to better understand and defend their faith! What you’re doing is marvelous and a model for all of us. May some of our readers be inspired by your example to follow suit and volunteer to lead such groups in their churches!

I hate to keep pounding the same point (see QoW #357), but your question seems to be based on the old conflation of moral ontology and moral epistemology. I think that keeping this distinction clear is perhaps the most important point in understanding the moral argument. So it bears repeating: “Moral ontology has to do with the objective reality of moral values and duties. Moral epistemology has to do with how we come to know moral values and duties. The moral argument is wholly about moral ontology; it says nothing about how we come to know moral values and duties.” In particular, it says nothing about how people came to know their moral duties prior to their hearing about the Ten Commandments.

So what is the objection supposed to be? You ask, “where do we get the rules for morality?” Understood as an ontological question, the answer I have defended is Divine Command Theory: whereas moral values are grounded in God’s essential nature, our moral duties are grounded in His commands to us. Notice that that is not an epistemological answer but an ontological answer: we have objective obligations and prohibitions because God has issued certain imperatives to us. How one comes to know the content of God’s moral imperatives is a separate question. Apart from such imperatives we would have no moral duties; but that is consistent with saying that we can be aware of our moral duties without being aware that God has issued such commands. If your question is interpreted epistemologically, there are all sorts of ways in which one might come to know one’s moral duties.

You then ask, “how did people know moral obligations prior to Mt. Sinai?” That’s an epistemological question. A more salient question would be how people could have had moral obligations prior to Sinai. That’s an ontological question. One answer to that question is that while the Ten Commandments codified God’s moral rules for Israel, this wasn’t the first time He had issued such commands. Or at least most of them: there’s no reason to think, for example, that people did have an obligation to keep the Sabbath prior to God’s commanding it at Sinai. As for the epistemological question, as you yourself note, Scripture tells us how people who are ignorant of the Ten Commandments can know their moral duties. In his letter to the church in Rome, Paul says, “When Gentiles who have not the law do by nature what the law requires, they are a law to themselves, even though they do not have the law. They show that what the law requires is written on their hearts, while their conscience also bears witness and their conflicting thoughts accuse or perhaps excuse them on that day when, according to my gospel, God judges the secrets of men by Christ Jesus” (Rom. 2.14-16). On Paul’s view you don’t have to be aware of the source of your moral duties in order to know your moral duties.

You seem to have reservations about this answer because it “gets into Christian theology which I find is too far of a mental stretch for some by simply showing how theism is necessary for moral obligations.” Now wait a minute! I’ve already said that the moral argument is about moral ontology and is independent of any answers to epistemological questions. But when you ask how people knew their moral obligations prior to hearing the Ten Commandments, you’re asking a scriptural question to which a scriptural answer is quite appropriate. Don’t let the mental limitations of those you’re dealing with cause you to back away from scriptural truth. They can understand it if you make it simple.

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