
Liberalism, in the sense of the liberal movement in the Christian church in the 1800s -- which still continues today as can be seen
here,
hereand in the emergent movement -- is a poison in the visible Christian church. I say the visible church, as there comes a point where liberals deny Christ, deny the Trinity, the resurrection, the virgin birth of Christ, the deity of Christ, deny penal substitionary atonement, or deny something else that invalidates the Gospel in the minds of those who believe it, and as such can no longer be considered to be Christian at all.
It is a sickness, a cancer, that spreads, among some that would lead them to turn away from the truth about God's words, denying its inerrancy, and eventually denying its power and truth. It is unfortunately, also fueled somewhat by the public school system.
In the early 1900s, John Gresham Machen, combated what was then modern liberalism, with his book Christianity and Liberalism. One of his points in that amazing book, which I will link to a free copy of at the bottom of this post, was that Liberal Christianity is not Christianity at all. Instead, it is a new religion that seeks to corrupt the Christian church. More Here...