Following up on his What is fundamentalism?, Roger Olson asks what liberal theology is. You can read more of his post at the link.
This is Roger’s really good book on it: The Journey of Modern Theology.
Here are Olson’s major themes for liberal theology:
In other words, according to Welch, and many others within the liberal tradition of modern Christianity, “the best of modern thought” is a source and norm for Christian theology (and ethics) alongside the Bible and tradition. And, if there is a conflict between the Bible and tradition, on the one hand, and the best of modern thought, on the other hand, the latter trumps the former. This is expressed very clearly by many liberal Protestant theologians.
Here are some “hallmarks” I see shared by most modern liberal Christians:
1) A tendency to reduce the Bible to “the Christian classic” that is “inspired” insofar as it is inspiring;
2) A tendency to reduce Christianity itself to ethics such that doctrine is an expression of collective opinion always open to revision in light of changing cultural conditions;
3) A tendency to embrace and promote individualism in spirituality and doctrine while insisting on certain controversial ethical positions as matters of justice and therefore beyond debate;
4) A tendency to deny miracles or “demythologize” them so that belief in no miracle is essential to authentic Christian existence;
5) A tendency to emphasize the immanence of God over God’s transcendence;
6) A tendency to believe in the essential goodness of humanity and to deny hell except as inauthentic existence in this life;
7) A tendency to interpret Jesus as different from other humans only in degree (e.g., more spiritually and ethically advanced) and not in kind;
8) A tendency to promote authentic Christian existence as a life of love only without judgment (except of “injustice”).