In case you didn’t know, Charles Finny had a profound influence on evangelicalism and American Christianity. It was Finney who popularized the “altar call,” a practice still used to this day. I would put him easily in the top-5, maybe in the top-3 most influential people in the history of American Christianity. In Mosaic of Christian Belief, Roger Olson has this to say about him:

In spite of his many great achievements, Finney’s expressed views on salvation were more consistent with semi-Pelagianism than with orthodox Christianity. He more than implied that gracious works of God, in and for individuals and groups of people, wait upon human initiative and that all people are capable by will power alone of repenting, exercising faith in Christ, and living virtually sinless, holy lives. Critics of Finney’s theology and revival methods are quite right to suggest that he became a major conduit of enlightenment rationalism, individualism and humanism into conservative evangelical Christianity. No doubt his motives were pure, but his theology was pernicious.(274)

Essentially, Olson is calling Finney a heretic.