Ere long Arianism and Socinianism were general among English Presbyterians (see Unitarianism).
A movement towards Arianism and then towards Socinianism (Joseph Priestley, Nath.
A Glasgow professor, the Rev. Mr Simson, was attacked for Arminianism and Socinianism as early as 1717; and the battle raged between the more severe Presbyterians - who still hankered after the Covenant, approved of an old work The Marrow of Modern Divinity (1646), and were especially convinced that preachers must be elected by the people - and the Moderates, who saw that the Covenant was an anachronism, thought conduct more important than Calvinistic convictions, and supported in the General Assembly the candidates selected by patrons, as against those chosen by the popular voice.
Before taking orders in 1658 he was in the habit of preaching as the champion of Calvinism against Socinianism and Arminianism.
In 1767 he was appointed to the charge of Mill Hill Chapel at Leeds, where he again changed his religious opinions from a loose Arianism to definite Socinianism and wrote many political tracts hostile to the attitude of the government towards the American colonies.
The withdrawal of members to form other churches in the neighbourhood and the intrusion of Socinianism almost extinguished the Charleston church about 1746.
In Socinianism (see below) we have perhaps the only instance of humanistic antecedents leading to the formation of a religious sect.
It disengages itself in the 17th century as Socinianism and in the 18th as Rationalism or Deism.
If Socinianism had challenged natural theology - Christ, according to it, was the prophet who first revealed the way to eternal life - it had glorified the natural powers of man; and the learning of the Arminian divines (friends of Grotius and Locke) had helped to modernize Christian apologetics upon rational lines.