The philosophical approach would be to ask if it would be possible for laws of nature to be truly necessary, that is independent of any other entity for their existence.
Here is a commentary on Avicenna's take on the matter Boiled down, the answer is that no, there cannot be more than one thing that is necessary in and of itself, because any entity that was necessary and of itself would need to be simple (that is without parts, since if it had parts the entity as a whole would depend on its parts) and for two entities to differ from each other, they would need to differ in some part.
Once you have shown that there can only be one entity which is necessary in itself you can show that that entity must be immaterial, immutable, infinite, omnipresent, perfect, eternal, goodness and truth itself, etc. And at that point it is pretty clear that you are talking about God, even if reason alone can't get you every truth of Christianity.
I'm not committed to that argument in particular, but the point is that this theory is making philosophical statements (those being: the laws of nature are necessary, and creation of life is a necessary consequence of those laws, which makes God superfluous), and must properly be countered by other philosophical statements.
That being said, most people who are likely to trot this out are probably not going to be willing to listen to philosophical arguments, though they will be more than willing to make them. So I don't know what the best rhetorical strategy would be. For people who aren't listening to you at all it would be to state why you would have to respond philosophically, and end the conversation until they are willing to hear you out. For people who are willing to listen to you on other matters I'm not sure what the most effective argument would be.
