William Wilberforce, while born into the Anglican Church, had converted to Methodism while a young man, but his mother had persuaded him to convert back to Anglicanism, as Methodists, like other evangelicals, were widely regarded as crude and fanatical by Britain's upper classes. When Wilberforce read Philip Doddridge's Rise and Progress of Religion in the Soul, he was struck by its entreaties to Christians to be active in the world, and to pursue their own purity. "You will be zealous especially," Doddrige wrote,
to correct what is irregular in yourselves, and to act to the utmost of your ability for the cause of God. Nor will you be able to look with an indifferent eye on the conduct of others in this view! ...[Y]ou will testify your disapprobation of everything in it, which is dishonourable to God, and injurious to men. And you will labour not only to reclaim men from such courses, but to engage them to religion, and to quicken them in it.
Wilberforce came to understand his privileged position in society as a God-given opportunity to correct what was wrong with England. While part of his focus was on moral reform in his home country, particularly among the growing classes of urban poor, he devoted most of his energies to the slave trade, the one institution he saw as more "dishonourable to God, and injurious to men" than any other.