The apostle Peter likewise voiced a similar strong warning:

“However, there also came to be false prophets among the people, as there will also be false teachers among you. These very ones will quietly bring in destructive sects and will disown even the owner that bought them, bringing speedy destruction upon themselves.

This apostasy from true worship and doctrine took place and, particularly from the fourth century, false, apostate Christianity flourished and became united with the State, becoming a state religion. The area in which it predominated came to be called “Christendom” (meaning “Christian dominion”). This was directly contrary to Christ’s words: “My kingdom is no part of this world,” and “they [Jesus’ disciples] are no part of the world.”​—John 18:36; 17:14.

History records that from that time on religious leaders have been the counselors, yes, often the directors, of national rulers. Where they could not exercise power they were willing to provoke revolution or warfare against those rulers resisting them. Today, where they cannot be in favored, powerful positions among national rulers, they are often prominent among groups rebellious against the established government.