The event peaked in August 1742 when a crowd of some 30,000[1] gathered in the 'preaching braes' – a natural amphitheatre next to the Kirk at Cambuslang – to hear the great preacher George Whitefield call them to repentance and conversion to Christ.
It was said that the ale houses filled up when it was his turn to preach outdoors in traditional Scottish "Sacramental Occasions" or "Holy Fairs", as they were called.
However, M'Culloch was keenly interested in Calvinist theology of conversion and followed closely the work of the great preachers and their effects in Britain and British North America.
Towards the end of January 1742, two men, Ingram More, a shoemaker, and Robert Bowman, a weaver, went through the parish, and got about 90 heads of families to sign a petition to the minister, asking that he give them a weekly lecture.
However, on Monday 15 February, all the Fellowships in the parish turned up at the manse and spent several days praying and discussing and wondering about the great events that were being reported from England and America.
On Thursday 18 February, the weekly lecture proceeded as usual, though it was noticed that the congregation were paying particular attention to the detail of the sermon.
Many who attended the sermons were seized with a strong conviction that they were sinners and experienced an horrific sense of future punishment, many "bewailing their lost and undone condition by nature; calling themselves enemies to God, and despisers of precious Christ; declaring that they were unworthy to live on the face of the earth; that they saw the mouth of hell open to receive them, and that they heard the shrieks of the damned".
They were "raised all at once from the lowest depth of sorrow and distress, to the highest pitch of joy and happiness, crying out with triumph and exultation…that they had overcome the wicked one; that they had gotten hold of Christ!"
M'Culloch needed help and many of the most prestigious Evangelical ministers preached in Cambuslang – in particular Alexander Webster, of Edinburgh, who conducted one of the first Statistical Accounts of Scotland and Robe of Kilsyth, where similar events took place.
(He was surprised, when he announced his text, to hear the rustle of Bibles being leafed through to follow him – an indication of the high rate of literacy among common Scots of the time.)
For some years, however, 18 February was kept, according to M'Culloch "partly as a day of thanksgiving for the remarkable season of grace to many in the British colonies, and particularly for this small corner, in the years 1741 and 1742; and partly as a day of humiliation and fasting for misimprovement (sic) of mercies; and especially for the backslidings of many, who then showed a more than ordinary concern about their souls, but have since fallen away, and turned as bad, or worse than they were before".
However, many of similar Calvinist views had recently left what they thought of as an "ungodly" church and had set up a rival Associate Presbytery.
A fierce and intemperate pamphlet war ensued – though the writers always professed a Christian concern for the truth and the well-being of men's souls.