As everything in Rome must serve the state, so the religion of Rome was a state institution, an established church.  But as the state can only command and forbid outward actions, and has no control over the heart, so the religion of Rome was essentially external.  It was a system of worship, a ritual, a ceremony.  If the externals were properly attended to, it took no notice of opinions or of sentiments.  Thus we find in Cicero ("De Natura Deorum”) the chief pontiff arguing against the existence of the gods and the use of divination.  He claims to believe in religion as a pontifex, while he argues against it as a philosopher.  The toleration of Rome consisted in this, that as long as there was outward conformity to prescribed observances, it troubled itself very little about opinions.  It said to all religions what Gallio said to the Jews:  “If it be a question of words and names and of your law, look ye to it; for I will be no judge of such matters.”  Gallio was a genuine representative of Roman sentiment.  With religion, as long as it remained within the limits of opinion or feeling, the magistrate had nothing to do; only when it became an act of disobedience to the public law it was to be punished.  Indeed, the very respect for national law in the Roman mind caused it to legalize in Rome the worship of national gods.  They considered it the duty of the Jews, in Rome, to worship the Jewish God; of Egyptians, in Rome, to worship the gods of Egypt.  “Men of a thousand nations,” says Dionysius of Halicarnassus, “come to the city, and must worship the gods of their country, according to their laws at home.”  As long as the Christians in Rome were regarded as a Jewish sect, their faith was a religio licita, when it was understood to be a departure from Judaism, it was then a criminal rebellion against a national faith[268].

The Roman religion has often been considered as a mere copy of that of Greece, and has therefore been confounded with it, as very nearly the same system.  No doubt the Romans were imitators; they had no creative imagination.  They borrowed and begged their stories about the gods, from Greece or elsewhere.  But Hegel has long ago remarked that the resemblance between the two religions is superficial.  The gods of Rome, he says, are practical gods, not theoretic; prosaic, not poetic.  The religion of Rome is serious and earnest, while that of Greece is gay.  Dionysius of Halicarnassus thinks the Roman religion the better of the two, because it rejected the blasphemous myths concerning the loves and quarrels of the heavenly powers.  But, on the other hand, the deities of Greece were more living and real persons, with characters of their own.  The deities of Rome were working gods, who had each a task assigned to him.  They all had some official duty to perform; while the gods of Olympus could amuse themselves as they pleased.  While the Zeus of Greece spent his time in adventures, many of which were disreputable, the Jupiter Capitolinus