This debate focuses on a moral argument for the existence of god, and ultimately comes down to an inference from moral intuitions to universal divine commands or divine moral preferences.
Cambridge philosopher Arif Ahmed debated Christian philosopher Glenn Peoples on Premier Christian Radio, on the topic of moral arguments for god.
Roughly, Peoples makes following argument:
1) If moral facts exist, they must have either a supernatural or natural basis
2) Moral facts do not have a natural basis
3) :. If moral facts exists, they have a supernatural basis
4) The most plausible supernatural basis of moral facts is a supernatural person
5) :. If moral facts exist, they are based in a supernatural person
6) Moral facts exist
7) :. A supernatural person exists
Editorial comment - This argument heavily loads the dice by taking moral facts to be propositions in the mind of a divine being, and then equivocating between moral facts (thus defined) and the ordinary human moral intuitions shared by most everyone who is not a sociopath. The obvious naturalist response might be that moral facts ought to be derived from causal connections between certain actions and their probable results.
Ahmed retorts to Peoples formal argument firstly by denying premise (6), explicating his honest (if highly unpopular) view that moral facts are not really facts in the ordinary sense of the term. He basically makes the case that all actual moral imperatives are actually of the form "If you desire X then you should do Y." They both back and forth on the nature of morality for quite a bit, calming, politely, and without zinging around cheap one-liners (ala Hitchens or D'Souza). Incidentally, Peoples fulfills Godwin's Law around 20 minutes in.
Overall, this was a high-quality philosophical debate and discussion, relatively free of rhetorical flourishes, personal attacks, and other extraneous verbiage. Both guests are focused and well versed on the topic at hand, while the radio host is clearly and humorously out of his depth. Definitely this one is recommended listening.