Gnosticism is not explicitly mentioned in the Bible, but it refers to a broad and diverse set of beliefs that emerged in the early centuries of Christianity, often seen as heretical by orthodox Christianity. The term "Gnosticism" derives from the Greek word "gnosis," meaning knowledge, particularly esoteric or spiritual knowledge. Gnostics typically believed that salvation comes through this special knowledge, which often included a dualistic worldview that posited a stark separation between the material and spiritual realms. They viewed the material world as inherently flawed or evil and believed that the divine could be accessed through inner enlightenment or revelation.In the New Testament, certain writings, particularly the letters of John, address and counter Gnostic ideas. For example, 1 John 4:2 emphasizes the importance of acknowledging Jesus Christ as having come in the flesh, directly opposing Gnostic beliefs that often denied the physical incarnation of Christ. Additionally, Colossians 2:8 warns against being taken captive by hollow and deceptive philosophy, which could be seen as a reference to Gnostic thought that undermined the sufficiency of Christ's work. The early Church Fathers, such as Irenaeus and Tertullian, also wrote extensively against Gnosticism, asserting the importance of apostolic tradition and the physicality of the Gospel message, thus framing Gnostic teachings as divergent from the core tenets of Christian faith.