What does the Bible say about the dangers of false teaching?

In Mark 8, Jesus warns His disciples to beware of the leaven of the Pharisees and of Herod, symbolizing the destructive nature of false teaching and self-righteousness. The Pharisees, despite their outward piety, were spiritually lost as they substituted genuine faith for mere religious observance. This warning highlights the peril of relying on works or outward appearance for justification, underscoring the importance of true salvation through faith in Christ, as understood in sovereign grace theology. Moreover, the leaven of Herod, representing politically motivated religion, cautions against the infiltration of human wisdom into the Church, which ultimately detracts from the truth of the Gospel.