Gnosticism - "Whadda ya Know?"
I spoke with someone once that believes their highest authority for knowledge of anything here, or hereafter, is an inner knowledge that just comes to them. That is what the Gnostics believed. You may not meet anyone claiming to be a Gnostic, but may meet someone who has knowingly or unknowingly adopted some of their heresies.
What is Gnosticism? The principles of Gnosticism pre-date the New Testament by a couple centuries and they contradict what it means to be a Christian. First, Gnostics assert that matter is inherently evil and spirit is good. Second, Gnostics claim to possess an elevated knowledge, a “higher truth” known only to a certain few. Gnosticism comes from the Greek word gnosis which means “to know.” Gnostics claim to possess a higher knowledge, not from the Bible, but acquired on some mystical higher plain of existence. Christians assert that there is one source of Truth and that is the Bible, the inspired, inerrant word of God, the only infallible rule of faith and practice (John 17:17; 2 Timothy 3:15-17; Hebrews 4:12). It is God’s written revelation to mankind and is never superseded by man’s thoughts, ideas, writings, or visions.
Gnosticism is based on a mystical, intuitive, subjective, inward, emotional approach to truth which is not new at all. It is very old, and as with all lies, originates with Satan. He calls God and the Bible into question and catches in his web those who are either naïve and scripturally uninformed or who are seeking some personal revelation to make them feel special, unique, and superior to others. The Apostle Paul said, “Prove all things; hold fast that which is good.” (1 Thessalonians 5:21) We do this by comparing everything to the word of God, the only Truth.