Pryce Davies preaching on the necessity of partaking of Holy Communion, Harris came to the conviction that he had received mercy through the blood of Christ.
Through his circulating schools he taught thousands in Wales to read the Bible and created a generation of people which would be receptive to Methodist ideas.
Harris and Williams undertook major preaching journeys, starting in South Wales but later venturing north.
As they preached they made converts, whom they then gathered together into organised groups of fellowships (known as seiadau (societies) in Welsh).
[citation needed] These groups were supervised by the leaders and were built into a powerful network within the Church of England.
The Welsh Methodist revival also had an influence on the older nonconformist churches, or dissenters—the Baptists and the Congregationalists—who in turn also experienced growth and renewal.