Christian heresy

When heresy is used today with reference to Christianity, it denotes the formal denial or doubt of a core doctrine of the Christian faith as defined by one or more of the Christian churches. It should be distinguished from both apostasy and schism, apostasy being nearly always total abandonment of the Christian faith after it has been freely accepted, and schism being a formal and deliberate breach of Christian unity and an offence against charity without being based essentially on doctrine.