The 
Ranters were an 
antinomian and spiritualistic English sect in the  time of the 
Commonwealth, who may be described as the remains of  the 
Seekers. Their central idea was 
pantheistic, that  God is essentially in every creature, but  though many of them  were sincere and honest in their attempt to express the  doctrine of the Divine immanence, they were in the main unable to hold the balance. They denied the authority of the Church, of 
scripture, of the current ministry and of  services,  calling on men to hearken to 
Jesus Christ within them. Many  of them seem to have rejected a belief in 
immortality and in a personal God, and in many ways they  resemble the 
Brethren of the Free Spirit in the 14th century. Their vague pantheism landed them in moral confusion, and many of them were marked by fierce fanaticism. How far the accusation of sexual immorality brought against  them is fair is  hard to say, but they seem to have been a really  serious danger to the government.  They were largely recruited from  the common people, and there is plenty of  evidence to show that  the movement was widespread. The Ranters came into contact and even rivalry with the early 
Quakers, who were often unjustly associated  with  them. The truth is that the positive message of the Friends helped to save England from being overrun with Ranterism.
In the  middle of the 19th century the name was often applied  to the Primitive Methodists[?], with reference to their crude and  often noisy preaching.
Updated from the 1911 Encyclopedia Britannica
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