The Social Gospel is a social movement within Protestantism that aims to apply Christian ethics to social problems, especially issues of social justice such as economic inequality, poverty, alcoholism, crime, racial tensions, slums, unclean environment, child labor, lack of unionization, poor schools, and the dangers of war. It was most prominent in the early-20th-century United States and Canada. Theologically, the Social Gospelers sought to put into practice the Lord's Prayer (Matthew 6:10): "Thy kingdom come, Thy will be done on earth as it is in heaven". They typically were postmillennialist; that is, they believed the Second Coming could not happen until humankind rid itself of social evils by human effort. The Social Gospel was more popular among clergy than laity. Its leaders were predominantly associated with the liberal wing of the progressive movement, and most were theologically liberal, although a few were also conservative when it came to their views on social issues. Important leaders included Richard T. Ely, Josiah Strong, Washington Gladden, and Walter Rauschenbusch. The term Social Gospel was first used by Charles Oliver Brown in reference to Henry George's 1879 treatise, Progress and Poverty, which sparked the single tax movement. The Social Gospel affected much of Protestant America. The Presbyterians described their goals in 1910 by proclaiming: The great ends of the church are the proclamation of the gospel for the salvation of humankind; the shelter, nurture, and spiritual fellowship of the children of God; the maintenance of divine worship; the preservation of truth; the promotion of social righteousness; and the exhibition of the Kingdom of Heaven to the world. In the late 19th century, many Protestants were disgusted by the poverty level and the low quality of living in the slums. The social gospel movement provided a religious rationale for action to address those concerns. Activists in the Social Gospel movement hoped that if by public measures as well as enforced schooling, the poor could develop talents and skills, then the quality of their moral lives would begin to improve.