Matthew Harrison Brady: But your client is wrong. He is deluded. He has lost his way.
Henry Drummond: It's a shame we don't all possess your positive knowledge of what is right and what is wrong, Mr Brady.
--Inherit the Wind
The Social Gospel movement is grounded in the belief that Christian ethics can be applied to solve social problems such as poverty, crime, alcoholism, and racism. The movement is consistent with postmillenial belief that the second coming of Christ would not occur until earthly wrongs were righted.
One way to advance the Social Gospel is through voluntary, charitable acts. However, the movement gained political traction in the late 1800s when Social Gospellers of primarily Protestant origin proposed that government could be used to cure social ills--Prohibition being one example. The Republican Party was first on board, but it did not take the Democratic Party long to follow suit.
As such, the Social Gospel became the religious arm of sorts for the Progressive movement that was revving up at the same time.
Although the 'official' Social Gospel movement is generally said to have withered in the first half of the 20th century, it is obvious that the central idea has not. In particular, the idea that government can be employed as an agent for social change persists in various religious and secular forms.