In the Gospel of Matthew, the devil presents Jesus with a trio of temptations. For the culminating incident, Satan offers "all the kingdoms of the world in their magnificence." Jesus refuses.
To Austin Rogers, this story has key political implications. "Christ denied using earthly power and government to accomplish his mission," he writes in his book The Third Temptation, "and since Christians are called to imitate Christ, we should do the same."
Through painstaking research and deft historical recounting, Rogers shows that intermingling the state's means with the church's ends has tended to hamper, not advance, the latter. As one scholar put it, the first three centuries A.D. saw Christians "bearing all trials with a fierce tenacity" and yet "multiplying quietly." Then the Constantinian revolution established the first Christian confessional state.
"In less than a hundred years," Rogers explains, followers of Christ "evolved from a powerless, persecuted minority to the empowered persecutors themselves." The result was an erosion of religious freedom, a loss of moral credibility, and a wave of inauthentic conversions, all of which weakened the church and diluted its message.
Fourth century Christians failed to heed the lessons of Jesus' third temptation. It's an open question whether 21st century Christians will do any better.