Adoptionism

Adoptionism, sometimes called dynamic monarchianism, is a nontrinitarian theological doctrine which holds that Jesus was adopted as the Son of God at his baptism, his resurrection, or his ascension. According to Epiphanius's account of the Ebionites, the group believed that Jesus was chosen on account of his sinless devotion to the will of God.

Adoptionism was declared heresy at the end of the 2nd century and was rejected by the Synods of Antioch and the First Council of Nicaea, which defined the orthodox doctrine of the Trinity and identified the man Jesus with the eternally begotten Son or Word of God in the Nicene Creed.

Bart D. Ehrman suggests inThe Orthodox Corruption of the Scripture that Adoptionist theology may date back almost to the time of Jesus.

The Gospel of Mark is believed by most modern scholars to be the first of the four canonical gospels to have been written, dating from the time of the fall of Jerusalem in AD 70. Mark gives prominent mention to the destruction of the Second Temple and appears to have provided source material for Matthew and Luke. Many details found in later writings do not appear in the earliest manuscripts of Mark, including the phrase "Son of God" at Mark 1:1.Ehrman notes that this places the first use of the title "Son of God" for Jesus at his baptism, suggesting that Mark's gospel may reflect early Adoptionist views. The words "Today I have begotten you" are omitted from Mark, however; it is therefore generally believed to have less Adoptionist tendencies than the lost, non-canonical Gospel of the Hebrews.

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