Though I am more interested in historical Christianity and have little interest nor much qualifications to enter into philosophical discussions, I did want to make a single piont.
I have seen this sort of argument that morals originate with and are defined by deity. However, if I might point out, historically, the early traditions describe a God who created physical and material things by virtue of using pre-existing matter (i.e. he did not create the matter out of “nothing’ – ex nihilo, but it had a prior existence as well). In terms of spirit for example, the pistis Sophia describes the spirit-intelligent as “self-willed matter”, which type of matter also had existence and was not an ex-nihilo creation.
My point is, that for such early Judeo-Christians, there were other things that had eternal existence as well as God himself (matter, spirit, etc). If the scientific maxim is true, that matter is not created or destroyed (from an absolute standpoint), then the matter itself may have has attributes associated with it that were not “created”. (i.e. mass, takes up space, etc...)
IF, “self willed matter” (or spirits, intelligence, etc) also has attributes that are inherent to it's existence, then it may have moral attributes that also simply are part of it’s existence.
Does either side of your two premises change if these early judeo-christians were correct that certain things, such as matter exist independently of God?
For example, if the early judeo-christians were correct that matter of different types (i.e. base matter/spirit/intelligence) and even God himself are simply part of existence itself, then can there be moral verities that are also simply part of existence?
For example, if God “creates” all things from “nothing”, (i.e. ex-nihilo), then he presumably can arbitrarily change conditions and say that, “the old evil is now good”, rape and murder and lying are now “good” and the things that used to be “good” are now “evil” and now rape and torture will now produce "joy" and "harmony", whereas before they produced pain and fear and suffering and unhappiness.
IF, however, there are moral verities that exist external to God then God cannot arbitrarily say that Rape and torture of an innocent child are now “good”. That is, he cannot change these moral rules arbitrarily and, if he did so, moral realities would not change, but instead, he would simply be an “evil” god like the other Gods he denounced for immoralities.
I’m not trying to say the early Christians were correct or incorrect in their belief that things are created from matter rather than from "nothing" /ex-nihilo or that the later Christians were correct in their belief that things are created from “nothing”, merely that the base beliefs change base premises. For example, Robin1 is, if I am correct, arguing from the standpoint of God having created all things ex-nihilo? (Please understand Robin1 that I really think your points are wonderfully well made and this is not meant as a critical point, merely an observation). Whereas, in this early Judeo-Christian tradition, God himself, must obey certain moral principles in order to remain a "good" god (i.e. he is bound externally as well).
Clear
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