a millennium in which reason was enchained, thought was enslaved, and knowledge made no progress.
During the two centuries in which they had been a forbidden sect the Christians had claimed toleration on the ground that religious belief is voluntary and not a thing which can be enforced. When their faith became the predominant creed and had the power of the State behind it, they abandoned this view. They embarked on the hopeful enterprise of bringing about a complete uniformity in men's opinions on the mysteries of the universe, and began a more or less definite policy of coercing thought. This policy was adopted by Emperors and Governments partly on political grounds; religious divisions, bitter as they were, seemed dangerous to the unity of the State. But the fundamental principle lay in the doctrine that salvation is to be found exclusively in the Christian Church. The profound conviction that those who did not believe in its doctrines would be damned eternally, and that God punishes theological error as if it were the most heinous of crimes, led naturally to persecution. It was a duty to impose on men the only true doctrine, seeing that their own eternal interests were at stake, and to hinder errors from spreading. Heretics were more
