The questions you are asking are usually classified as "meta-ethics".  Meta-ethics asks about things like the nature of moral propositions, the knowability of moral truths, and other various topics that are focused on the nature of moral truths and systems. 

For whatever reason it seems that most philosophers who ask questions like this get mired in questions about ethics without ever arriving at ethics, if that makes sense.  Since we all have a sort of morality and all live in a world steeped in moral language and judgments, I would recommend starting your moral inquiry from that point of view, as opposed to something like metaphysics or epistemology where it seems easier to start from a purely abstract and theoretical point of view.  This was Socrates' method.  For example it might be easier/more useful to start by reading a text on virtue ethics or utilitarianism than by looking for a systematic text on abstract questions about the foundations of norality.

As far as a text dealing with the questions you are asking about, which are indeed good questions, I will let others offer recommendations.  None of that is to discourage you from asking about meta-ethics.  Just offering my teo cents.

Probably Plato, Schopenhauer, and Nietzsche.  Although Sextus Empiricus and Zhuangzi, the ancient Daoist, both get an honorable mention.

Marty wrote:

Look, what stops me from saying that God is a spatial-temporal being, but just redefine spatial-temporal to mean spatial-temporal², where spatial now means a really all-powerful spatiality that cannot be divisible, or composite? Or saying a really all-powerful temporalness that exists always but temporally. I can evoke a every-present moment. But we'd say, "Well no, because that's just a contradiction given that spatial means something that's composite and divisible, and temporal meaning something that flows through time." Likewise, beliefs (any that we know of at least) can all fail due to their intentional and normative nature. 

If you were speaking analogically, nothing would stop you from saying those things.  It wouldn't  be clear or precise but it would be a good first attempt at defining what it means to be omnipresent and eternal.

If you were speaking literally, what would stop you from saying that God is spatio-temporal would be the meanings of those words (or perhaps you're a Mormon!)

It seems you just don't like/want to accept analogical reasoning, which, to be fair, is an interesting criticism.   I just don't see any particular problem with God's "beliefs".

I can't speak for Aquinas specifically, but in general the Ancient and Medieval view concerning free-speech is that speech serves a purpose, namely expressing the truth.  If someone says something false, and offers no argumention for their statements, I can't imagine someone like Aquinas or Aristotle defending one's right to do so.  This seems to based on a fundamentally non-liberal conception of the state, which is so far removed from our contemporary idea of the state, that Aquinas and others probably wouldn't recognize free-speech as an issue.

An issue that does concern Ancient and Medical philosophers (and which is immensely overlooked in discussions of protests and political speech) is that of rational discussion vs. rhetoric.  Often times when people claim, "I have a right to free speech" what they mean is "I want to express an irrational opinion in a highly emotional manner and not be questioned in any way."  This is more properly a question of rhetoric and sophistry the it is of free speech.

Jeremy, I believe so.  I think the author starts with analytic dilemma since Quine of wanting to take metaphysics seriously, but not having anything like a method.  I take it the author starts by looking at biology (I'm not certain what exactly this means) and argues that things like teleology and natural kinds and other sorts of scholastic ideas and principles are justified, ultimately arguing that the scholastics had a better understanding of and methodology concerning metaphysics than we do.   I've gathered this from a couple reviews on Google.  The description I gave could be incorrect.