Most people would agree that to be excellent at something starts with knowing and putting into practice the fundamentals, the basics, in other words the truth of that particular field of endeavor.
The fundamentals can be considered the Words by which we can achieve/become true and good. So for people called to be children of God, it’s important to get the fundamentals right—from the right place, guided by the Spirit of truth. Otherwise being a fundamentalist can be unChristian.
Pope Francis recently said (on the plane back from Africa) that “we Catholics, we have a few, even many fundamentalists. They believe they know the absolute truth and corrupt others, I can say this because this is my Church.”
Pope Francis’s language is imprecise. It sounds like he’s speaking not about those who incorrectly read the bible literally (with particular lines eclipsing whole truth), but rather about those who claim to know the truth, which we are indeed called to know. Pope Francis’s flight from the truth (in this and other proclamations) puts him at odds with the Holy Spirit.
The words of Jesus: “The truth will make you free” (Jn. 8:32) must enlighten and guide all theological reflection and all pastoral decisions in this area.
The truth which comes from God has its center in Jesus Christ, the Savior of the world. From Him, who is “the way, and the truth, and the life” (Jn. 14:6), the Church receives all that she has to offer mankind. Through the mystery of the Incarnate Word and Redeemer of the world, she possesses the truth, concerning man and his freedom…Truth, beginning with the truth about redemption, which is at the heart of the mystery of faith, is thus the root and rule of freedom, the foundation and measure of all liberating action. Instruction on Christian Freedom and Liberation, 1986