19+ Cs Lewis Spiritual Warfare Quotes. Lewis cautioned against both imagining a demon behind every tree. Lewis questioned his proclamation of being an atheist since he converted back to christianity 20 years later. Lewis institute in chicago.the c.s. Lewis and i was reminded of the spiritual warfare that we face . Lewis quotes on god, jesus christ, and christianity. So we define spiritual warfare as the battle for the mind. Lewis is one of the most quoted authors on twitter. Speaker, karl kj johnson, lt.col., usmc (ret.) director of the c.s. Maybe screwtape letters opened your eyes to a unique viewpoint on spiritual warfare. Loving people is the highest level of spiritual warfare that we could ever do." — joyce meyer quotes from quotefancy.com.