John Howard Yoder makes the striking observation that after the Constantinian shift the meaning of the word "Christian" changes. Prior to Constantine it took exceptional courage to be a Christian. After Constantine it takes exceptional courage not to be counted as a Christian.... After the Constantinian establishment, Christians knew that God was governing the world in Constantine, but they had to take it on faith that within the nominally Christian mass there was a community of true believers. No longer could being a Christian be identified with church membership, since many "Christians" in the church had not chosen to follow Christ. Now to be a Christian is transmuted to "inwardness."

p. 62 - Matthew (2006)

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