Greco-Roman polytheism as such had no concrete theology or moral code tethered to its established rituals.  This left people considerably free to interpret a reality of a world full of gods.

 

For most people, the gods were individual, supernatural beings who influenced the universe, and therefore were in a position to grant blessings and calamities on humanity.  Whether as individuals or - much more often - as communities of worshipers, they entreated these supernatural beings for a wide variety of favors, most rather practical.  Military victory, good harvests, good health and cure for plagues, prosperity and welfare,  safe travel, knowledge of the future, etc. - these were the concerns of the ancient human.  

 

What did these gods require in return for their services? Not much.  Ritual purity; a temple or shrine; and a festival every month, year or several years, usually involving a sacrifice and in some occasions contests of skill.   Some deities like Zeus, Apollo or Athene might also generally promote a stable social order, but they stopped short of thrusting a detailed moral code on their adherents.  In the sum of things, the people honored the gods through rituals, and in return the gods were thought to confer favors, or at least refrain from doling out their wrath.

 

Those wanting a more personal religion had to find it outside the constraints of this straightforward communal contract with the gods.   The evidence suggests plenty of people needed or wanted a more personal religion, thus infusing deities who offered such with no small amount of popularity.   Dionysus, Kore, Isis, Cybele, and Mithras were deities who offered either a better afterlife or a spiritual transformation - or in some cases both.    Adherents had to be initiated into the secret rites and understandings of the deity, and follow any proscribed ethical code and ontology offered by the cult.    Relative to the communal cults, these savior deities offered much, but demanded much.   

 

One could belong to the traditional communal cults and these private mystery groups. In fact, many did.  The mystery gods were demanding, but not to the point of compelling an individual to sever all ties with family and community.  Most individuals would not want to totally abandon their community and its chosen patron deities.  And even if they clandestinely harbored such a wish, to act openly in doing so would have incurred the wrath of their fellow citizens and the civic officials.

 

Then there were the philosophers and other associated intellectuals, who interpreted  Greco-Roman religion through the light of Hellenic philosophy or Greco-Egyptian theurgy.  For them religion had a definite theology, usually pantheistic in nature and quite often involving several layers of reality.  On the whole the deities were less individual supernatural beings in their own right and more metaphors for currents of the cosmos.  The cosmos itself was the reality, and in some cases a maze to be navigated by those in possession of the correct wisdom or magical techniques.  This philosophy of the educated also usually imbued a definite moral code on its practitioners, which can be described broadly as humanistic in concern and rational in temperament.
 

The religion of the philosophers, while a valid level of Greco-Roman religion,  receives an attention out of proportion to the number of people who actually practiced it.  As the common people did not leave books for posterity, scholars have no choice but to focus on primary texts written by elite males.    Then too there is the fact that these intellectual writings provided the ground in which Christianity developed.     But it should be noted that the average peasant or lower class urban dweller in Greek and Latin speaking lands most likely did not have the ability or inclination to follow these highbrow concepts of religion.

 

My own practice incorporates the first and second strands.  Within the privacy of my own home, and before my bedroom shrine, I make simple offerings to such gods as Hermes, asking for such mundane matters as luck and prosperity, and assurance in my travels.   But then too I honor Isis as a savior deity, which involves not only daily offerings but the internalization of a certain ontology.

 

I have no qualms with those holding a philosophical or theurgic view of the gods.  But invariably on pagan lists I encounter those who suggest we all - not just these individuals themselves - should look at the gods and our relationships to them through that filter.  I have to say I am not interested, and that furthermore I do not find such things necessary.