“The Empire required all non-Jews to participate in Roman civil religion. The Romans tolerated all kinds of religious practices, but no matter what your religion was or where you came from, the government also expected you to take part in the ceremonies and public events of Roman society. Such events were somewhat like the Fourth of July parade In the United States. It did not matter what religion you were: it was part of your duty as a citizen to join in.

Citizens who did not participate in the civil religion (the Jews, of course, were exempted) faced serious consequences, even apart from any death penalty. Those who did not take part in the civil ceremonies would significant economic opportunities. They would be ostracized from the trade guilds, in which people networked to build their businesses. When jobs opened up, the best would be reserved for the “good citizens” of the area. Noninvolvement also had political consequences. Civic positions required people to encourage and lead out in the civil religion. Without political position, Christians had no or little ability to influence the development of society or to improve their position within it. Lack of involvement in the civil religion also forfeited social opportunities. Just as today, the party crowd was also the “in crowd” and Christians had a hard time becoming “in.” As a result, those who refused to participate in Roman civil religion became poor, powerless, and social outcasts. These were very real issues to anyone who considered becoming a Christian in first-century Asia Minor.”
(Jon Paulien, The Deep Things of God, p.24-25)