Poisoned Souls
by A. W. Tozer
...The movement from orthodoxy to liberalism is usually slow, almost too slow to be perceived... Unbelief enters the soul by a slow seepage; the toxin gets through the walls of the soul by a kind of spiritual osmosis so that the victim is well poisoned before he or she notices it, and the pathological condition that results usually makes it impossible for that person to know what is wrong. I have never known of a single instance where a man or woman accepted modernism as a result of a spiritual experience. Rather it is the lack of such experience that exposes the soul to the in-seepìng of the poison of unbelief.
...The liberal can never be quite sure of anything - it is contrary to his or her whole philosophy to be certain. Only the true Christian is sure. He or she has seen the sun rise, and it takes more than the contentions of the pseudo-learned to destroy the brightness of this person's faith.
from chapter 33 of This World: Playground or Battleground?
