Christian Heresies

The Christian versions of Gnosticism were considered serious heresies.  Gnosticism has never entirely disappeared, and can be seen in the traditions of alchemy and astrology, and even in modern times in the works of Carl Jung.

Adoptionism says that Jesus was a human being who was "adopted" by God at his conception, at which point he developed a divine nature. Later versions sometimes suggest that he was adopted later, such as when he was baptized by John the Baptist.

Marcionism was a religious movement based on the teachings of the 2nd-century heretic Marcion of Sinope. While none of Marcion’s writings have survived to the present, we know of his teachings through several early Christian writers including Justin Martyr (AD 100—165), Irenaeus of Lyons (AD 130—200) and Hippolytus (AD 170—235).

Sabellianism is named for its founder Sabellius. It is sometimes referred to as modalistic monarchianism. The father, son, and holy ghost are three modes, roles, or faces of a single person, God. This, of course, implies that Jesus Christ was purely divine, without humanness, and therefore could not truly have suffered or died.

The name comes from the Greek word dokesis, meaning "to seem."  Along the same lines as Sabellianism, Docetism says that Christ was not a real human being and did not have a real human body.  He only seemed to be human to us.

Manicheanism is actually a separate religion that blends Christianity with Gnosticism, Mithraism, neo-Platonism, and even Buddhism. It was considered a very serious heresy. It survived well into the Middle Ages, where it strongly influenced the Bogomils in the Balkans and the Cathars in southern France.