Anthropianism – The Anthropians believed that Jesus Christ was merely human. This heresy was rejected in the First Council of Nicaea (AD 325), which was convened to deal directly with the nature of Christ's divinity.
Arianism – A presbyter in Alexandria, Arius (c. 250-336) denied the divinity of Jesus Christ. He taught that Jesus was only the highest created being, created out of nothing in time, and was not of the same substance as the Father. Arius's bishop, Alexander of Alexandria (d. 328), strongly opposed this heresy. The Arian heresy was condemned at the First Council of Nicaea.
Donatism – Named for their second leader Donatus Magnus (d. c. 355), the ordained Bishop of Carthage in 313. The Donatists taught that moral unworthiness (even if repentant) invalidated the sacraments. They refused to accept the sacraments and spiritual authority of church leaders who were traitors during the persecution of Christians under Diocletian.
Ebionites – The Ebionites regarded Jesus Christ as the Messiah while rejecting His divinity. They also insisted on the necessity of observing circumcision and the Jewish Law. The rejected the Apostle Paul as an apostate from the Law. The early Christians deemed the Ebionites as heretical Judaizers.
Gnosticism – Gnosticism was the primary heresy during the time of the Pre- Nicene church. The term “gnostic” derives from “gnosis,” which means “knowledge” in Greek (cf. 1 Timothy 6:20-21). The Gnostics claimed that the apostles had secretly passed down this revealed knowledge (gnosis) to few chosen followers.
Gnostics taught that the earth and mankind were created by an imperfect “god” they called the Demiurge, other than Christ's Father, the good “god.” According to them, the Demiurge was the “god” of the Old Testament. Because of the inferiority of the Demiurge, all matter, whether it be the physical universe or the human body, is evil. Thus, all material things (including the flesh) are inherently corrupt and incapable of salvation. But the Gnostics were privy to the secret knowledge of salvation.
Gnostics taught that the Father of Jesus sent his Son to show humanity the way to salvation. Since the flesh is inherently flawed, according to the Gnostics, Jesus Christ never actually became man (cf. 1 John 4:3; 2 John 7). Docetism, a doctrine closely related to Gnosticism, stated that Jesus Christ was a spirit and had only taken on the illusion of flesh. The belief was mentioned in a letter by Bishop Serapion of Antioch (c. 197–203), who discovered the doctrine in the Gospel of Peter, and later condemned it as a forgery. Other Gnostic teachers taught that there was an actual man named Jesus, whose body the Son of God inhabited—only to abandon Jesus at the crucifixion.
Because matter was inherently evil, most Gnostic teachers rejected the doctrine of the resurrection of the body, the intermediate state of the dead, and the physical sacraments of baptism and communion. Some Gnostic groups practiced rigorous asceticism, while others were notoriously sinful.
Some of the foremost Gnostic teachers and sects of the first three centuries are listed below:
First Century:
• Simonians – It was said that all sorts of heresies “derive their origin” from Simon Magus, the “father of all heretics,” who made an appearance in Acts 8:9-21.
• Cerinthus – A Gnostic teacher who flourished around 100, Cerinthus taught that the world was made by a power separated from God and denied that Jesus was born of a virgin. Cerinthus was also devoted to carnal pleasures.
• Nicolaitans – The Nicolaitans were the followers of that Nicholas who was one of the seven first ordained to the diaconate by the apostles (Acts 6:5; Revelation 2:6, 15, 20). They led lives of indulgence, practiced adultery and ate things offered to idols.
Second Century:
• Basilideans – During the first half of the second century, Basilides was one of the foremost Gnostic teachers who lived in Alexandria. Basilides taught that Christ only appeared as a man and that Simon the Cyrenian was crucified in his place.
• Carpocratians – A magician and a fornicator, Carpocrates was one of the leading Gnostic teachers who lived in Alexandria. He claimed that the world was created by angels and that Jesus was just like other men.
• Marcionites – The Marcionites were a sect founded by the heretic Marcion (c. 85-160), who rejected Jesus' birth from Mary. Marcion incorporated many Gnostic beliefs such as the rejection of the Old Testament and the Hebrew “god” in favor of the New Testament “god.” Marcion established a “canon” which consisted only of the Gospel of Luke and the epistles of Paul, and even these he altered. The Marcionites also forbid to marry (cf. 1 Timothy 4:1-3).
• Valentinians – The Valentinians were a Gnostic and dualistic sect founded by an Egyptian named Valentinus (c. 100-160), one of the foremost Gnostic teachers of the early second centuries. He taught that Christ had a heavenly or spiritual body, and assumed nothing from the virgin Mary. He also constructed an elaborate cosmology of male- female aeons who supposedly govern the universe. The Valentinians also said that the resurrection was already past (cf. Timothy 2:18).
Third Century:
• Manichaeism – Manes (c. 216-276), also known as Mani or Manichaeus, founded this Persian heretical sect that incorporated many Gnostic doctrines. It was a highly dualistic religion stating that good and evil are equally powerful, and that material things are evil. He believed in two “gods,” one who is “just” and the other “good.” Manes denied that Jesus was born of the virgin Mary. They also abstained from meat and marriage (cf. 1 Timothy 4:1-5). Manichaeism is dealt with as heresy by the early Christians.
Monarchianism – Also known as Modalism, Patripassianism, and Sabellianism, it refers to the belief that the Father, Son, and Holy Spirit are three characterizations of one and the same person, rather than three distinct persons in the Trinity. Two of the early teachers of monarchianism were Noetus and Praxeas, later refined by Sabellius. The early Christians wrote in opposition to this heresy because it challenged trinitarian orthodoxy.
Montanism – In the second century, Montanism was based on the new revelation of the “prophet” Montanus. The Montanists referred to their movement as the New Prophecy, but the Church usually called them Phrygians, Cataphrygians, or Montanists. Montanus claimed to be the Paraclete or Comforter whom our Lord promised to send. After the death of Montanus, the sect was led by two self-proclaimed prophetesses, Priscilla and Maximilla. In the Montanist period of Tertullian's life, various false and distinctly Montanist teachings are found in his writings such as new revelations, Christians should not flee persecution, no second marriages after death of a spouse, and no forgiveness for post-baptismal sins. Montanists also sought out ecstatic spiritual experiences. But the early Christians denounced the Montanist movement.
Novatianists – In the third century, the Novatians were a sect founded by Novatian. They pridefully called themselves the title of “the Pure” and were marked by their rigorous discipline. The Novatianist sect refused to re-admit to Communion those Christians who had denied Christ in persecution or fallen away. They allowed no place for the lapsed repentance, not even if they did everything required for genuine confession and conversion.