The correct answer to this open question is the following.
Rauschenbusch argued that “the salvation of individuals” is not sufficient to address social problems because that was a promise for the afterlife. People's problems had to be addressed to improve their conditions.
We are talking about Baptist pastor and philosopher, Walter Rauschenbusch(1861-1918). He was part of the movement known as the Social Gospel, which invited people to think that social conditions had to improve to have a better and just life, not only under the promise of heaven. His ideas transcended and influence civil rights leaders like Dr. Martin Luther King Jr.