"the great business of the church is to reform the world," said which revivalist

Charles Grandison Finney was the revivalist who said: "the great business of the church is to reform the world,"

Charles Grandison Finney was an American Presbyterian, then Congregationalist, minister and religious writer.
He is mainly known for being the 'Father of Modern Revivalism'. He was a main leader during the "Second Great Awakening" in the United States.