Reading de Coulanges The Ancient City is fascinating. In describing the attitude ancient paganism produced toward your neighbor, he observes,
The religion of these primitive ages was exclusively domestic [worshiping ancestral gods -- sw]; so also were morals. Religion did not say to a man, showing him another man, That is thy brother. It said to him, That is a stranger; he cannot participate in the religious acts of thy hearth; he cannot approach the tomb of thy family; he has other gods than thine, and cannot unite with thee in a common prayer; thy gods reject his adoration, and regard him as their enemy; he is thy foe also. (p. 76)
There was no basis for “society” aside from the State. Private religion destroyed anything like true communion between man and man. No wonder Paul persists in emphasizing the “one-anotherness” of the gospel. The reality of being “one” in Christ Jesus, was staggeringly revolutionary.