Liberal Christian theology permeates mainlines denominations and progressive circles of the church to this day. But what is liberal theology? What are progressive Christians progressing toward, and what are they leaving behind? In Against Liberal Theology, professor and theologian Roger E. Olson warns progressive and mainline Christians against passively accepting the ideas of liberal theology without thinking through the consequences. In doing so, he examines the basic beliefs of the Christian faith, the main ideas of liberal theology, the way today's mainline and progressive Christianity relates to classic liberalism, and how classic Christian faith and liberal Christianity connect and contradict. Following in the footsteps of Gresham Machen's now-classic Christianity and Liberalism 100 years ago, Olson worries that liberal Christianity may not be Christianity but a different religion altogether. After examining the origins of liberal theology in the nineteenth century, Olson examines how liberal theology views: Sources of truth The Bible God Jesus Christ Salvation The Future Gentle but direct, Olson provides an even-handed assessment and critique of the ideas of liberal theology and worries that liberal Christianity has strayed too far from the classic Christian orthodoxy of the fathers and creeds to be considered "Christian" at all.