Paganism has little to offer.
You cannot build a society and community without justice.
Here are a few section headings which give the flavour of Augustine's argument.
Calamities befell the Romans when they worshipped the pagan gods before Christianity displaced them
Pagan gods had no moral teaching for their worshippers; in fact pagan rites were full of obscenities
The conclusions of philosophers are ineffective as they lack divine authority.
The Romans ought to have realised that gods who demanded obscene shows in their worship deserved no divine honours
Cicero and Scipio are invoked to press the point that one cannot have a commonwealth [=weal of the community] without justice. A community is
``not any and every association of the population, but "an association united by a common sense of right and a community of interest" (De Rep)''
The vicissitudes of history depend not on the favour or opposition of demons, but on the judgement of the true God.
The evil spirits encourage crime by giving it the authority of their supposedly divine example.