To every _proselyting_ religion the sentiment is so natural, that no divine spirit is needed to originate and establish it.

Mohammedans also have a conscience against enslaving Mohammedans, and generally bestow freedom on a slave as soon as he adopts their religion.

But no zeal for _human_ freedom has ever grown out of the purely biblical and ecclesiastical system, any more than out of the Mohammedan.

In the middle ages, zeal for the liberation of serfs first rose in the breasts of the clergy, after the whole population had become nominally Christian.

It was not men, but Christians, whom the clergy desired to make free: it is hard to say, that they thought Pagans to have any human rights at all, even to life.