Keeping chaos at bay

[P]articipation in the reverencing of household gods (the Lares dometici) was expected of all members of the Roman household. It was considered an important expression of solidarity with the others of the household in securing its continuing safety and welfare. Likewise, participation in the honoring of the tutelary deities of one’s city in sacrifice, processions, and other rituals was an important expression of solidarity at that level. For at least many in the general populace, these city gods were guardians against such risks as plague, fire, or other disasters. So, refusal to participate in the reverence due these deities could be taken as a disloyalty to your city and as a disregard for the welfare of its inhabitants. Further, there were gods believed to uphold and legitimate the larger Roman imperial order. Indeed, in the case of the goddess Roma, there was a deity that embodied the Roman order. So, to refuse to worship these deities could be taken as a deeply subversive action or at least a disregard for the political order. To repeat the point for emphasis, when pagan converts withdrew from the worship of the gods that they had formerly worshipped, this was a particularly acute matter, much more objectionable than Jews’ refusal to worship any deity but their own. The latter was an ethnic peculiarity, but that gave no justification for non-Jews to shirk their inherited responsibilities to their own gods.— Destroyer of the gods: Early Christian Distinctiveness in the Roman World, pages 54–55