So I've recently realized that the ethical challenges to Islam can be categorized in a certain way, each category having a common core of similarities. Here are the four categories of ethical challenges to Islam:
1. The Problem of suffering in its many varieties
2. The argument from Divine Hiddenness
3. Ethical complaints against specifically Islamic theological (e.g. the problem of hell) and ethico-legal (e.g. slavery and concubinage) positions
4. The challenge of developing a satisfactory Divine Command Theory of ethics.
All of these questions and discussions focus on the same theme: Is it justified to believe that God is the supremely ethical (perfectly good) being? Let's look at their interconnectedness in a bit more depth.
(4) focuses on a number of things, the two most important being the so-called moral argument for the existence of a supremely ethical being, and trying to answer the modality or the howness of God's command or nature imparting values and excellence and rightness on created things or actions. The latter involves independent theorizing (e.g. positing a form of theistic platonism, like Robert Adams did, in explicating the notion of the world's excellences being derived from God's supreme goodness- who, in Platonic language, is just the personal form of Good), as well as responding to contentions like the Euthyphro's dilemma. The project of (4), therefore, is to lend credence to the idea that God is supremely good and the source of all good.
1, 2, and 3 all seek to challenge this idea in various ways. 3 appeals to specific revelation- if we believe our moral sense mirrors God's in some significant yet incomplete way, then how do we square ethical scruples with what scripture says? 2 is very similar, except it appeals to 'general revelation'- the book of the world- to try to argue for the same case. We see concubinage being legalized in scripture, but the supremely ethical being wouldn't make these commands. We see seemingly gratuitous suffering, but the supremely ethical being wouldn't allow it.
2 has its own motivations as an argument, but its strength is brought out particularly in context of the problem of evil, especially the problem of particularly horrifying instances of evil. If there's a God who loves us, and if He has reasons beyond our ken to allow these sufferings, wouldn't we expect Him to communicate those reasons to us?
Based on this analysis, I suggest these ethical aspects of natural theology should be studied on its own. Let's leave aside 3 for a while, since we're talking about theism in general or natural theology. Most often, 1 and 2 are discussed as a part of atheology, while 4 as a part of natural theology. But I don't find that association to be very convincing. For one, most arguments from natural theology don't actually prove the ethical nature of God. They only establish the existence of a generalized, even deistic, creator-designer who is at best intimately involved with human existence. This may lend plausibility to the thesis of Him being ethical, but no explicit proof is offered.
Many people may say the moral argument proves that a supremely ethical being exists, but I never found that approach convincing. It just strikes me as too far-fetched to import the existence of an entire supernatural being into our ontology just to account for the objectivity of our morality. Rather, a much more nuanced approach suggested by Robert Adams is the following. The moral argument should be produced only when we have settled the case for deism, when we have proved that a personal creator-designer interested in our existence exists. The moral argument should not contribute to, or form a part of the cumulative impact of, the case for deism in any way. Rather, it should only serve to shed light on the character of the deity whose existence we've already established. This approach is much more plausible, since the conclusion isn't ontologically that significant to the extent it seems to outstrip the evidence offered. We already established that a deity exists, we know it's personal, but we're on the fence on its moral leanings. The moral argument can settle the debate nicely.
Even more importantly, neither the POE or Divine Hiddenness detracts from the case of deism in any way. This point has been made by proponents of Intelligent Design for a long time- malevolent design is still design.
So in conclusion, the natural theology discussion should be divided into two separate parts-
1. Arguments for and against deism
2. Arguments for and against the moral character of the deity.
EDIT: Something should be amiss if I didn't mention some references for all this.
1. Divine Command Theory of Ethics:
- Finite and Infinite Goods: A Framework of Ethics by Robert Merrihew Adams
- A Theory of Virtue: Excellence in Being for the Good by Robert Merrihew Adams
- Kierkegaard and the Ethics of Love by C. Stephen Evans
- (Paper) Divine Will/Divine Command Theories and the Problem of Arbitrariness by Thomas L. Carson
2. Problem of Evil:
- The Problem of Evil by Peter van Inwagen
- Problem of Evil: A Reader (essay collection) by Mark Larrimore
- The Evidential Argument from Evil by various authors, edited by Daniel Howard-Snyder
- The Blackwell Companion to the Problem of Evil by various authors, edited by Justin McBrayer
- Nature Red in Tooth and Claw: Theism and the Problem of Animal Suffering by Michael Murray
- (Paper) Must God Create the Best? by Robert Merrihew Adams
- (Paper) Is theism compatible with gratuitous evil? by Daniel Howard-Snyder
- Various other papers by Peter van Inwagen and Daniel Howard-Snyder
3. Problem of Hiddenness:
- Divine Hiddenness: New Essays edited by Daniel Howard-Snyder and Paul K. Moser
- Various essays and papers by Daniel Howard-Snyder