The Social Gospel is not the gospel of the Bible.
What is the gospel?
What truths does it involve? How simply can the gospel be preached and still be sufficient to save?
In other words, what are the gospel absolutes or the non-negotiables of salvation?
Trying to simplify the gospel is what many mainstream Evangelicals are obsessed with today. The popular discussion is how to make the message so simple and basic that anyone can believe it. And with as little trouble as possible.
Frankly, it would be very easy for me to go off on a rant about the foolishness of this obsession. But I will try to hold that back, somewhat, and provide an answer.