Adoptionism, also called dynamic monarchianism, is a Christian nontrinitarian theological doctrine which holds that Jesus was adopted as the Son of God at his baptism, his resurrection, or his ascension. Adoptionism, also called dynamic monarchianism, is a Christian nontrinitarian theological doctrine which holds that Jesus was adopted as the Son of God at his baptism, his resurrection, or his ascension. Adoptionism is one of two main forms of monarchianism (the other is modalism, which regards 'Father' and 'Son' as two historical or soteriological roles of a single divine Person). Adoptionism denies the eternal pre-existence of Christ, and although it explicitly affirms his deity subsequent to events in his life, many classical trinitarians claim that the doctrine implicitly denies it by denying the constant hypostatic union of the eternal Logos to the human nature of Jesus. Under adoptionism Jesus is currently divine and has been since his adoption, although he is not equal to the Father, per 'my Father is greater than I' (John 14:28). and as such is a kind of subordinationism. Adoptionism is sometimes, but not always, related to denial of the virgin birth of Jesus. The New Testament writings contain two different Christologies, namely a 'low' or adoptionist Christology, and a 'high' or 'incarnation Christology.' The 'low Christology' or 'adoptionist Christology' is the belief 'that God exalted Jesus to be his Son by raising him from the dead,' thereby raising him to 'divine status.' The other early Christology is 'high Christology,' which is 'the view that Jesus was a pre-existent divine being who became a human, did the Father’s will on earth, and then was taken back up into heaven whence he had originally come,' and from where he appeared on earth. The chronology of the development of these early Christologies is a matter of debate within contemporary scholarship. According to the 'evolutionary model' c.q. 'evolutionary theories,' as proposed by Bousset, followed by Brown, the Christological understanding of Christ developed over time, from a low Christology to a high Christology, as witnessed in the Gospels. According to the evolutionary model, the earliest Christians believed that Jesus was a human who was exalted, c.q. adopted as God's Son, when he was resurrected, signaling the nearness of the Kingdom of God, when all dead would be resurrected and the righteous exalted. Adoptionist concepts can be found in the Gospel of Mark, in which the birth of Jesus and the epithet 'Son of God' are absent in some early manuscripts, suggesting that the concept of the Virgin Birth of Jesus had not been developed or elucidated at the time Mark was written. Later beliefs shifted the exaltation to his baptism, birth, and subsequently to the idea of his eternal existence, as witnessed in the Gospel of John. Mark shifted the moment of when Jesus became the son to the baptism of Jesus, and later still Matthew and Luke shifted it to the moment of the divine conception, and finally John declared that Jesus had been with God from the beginning: 'In the beginning was the Word'. Since the 1970s, the late datings for the development of a 'high Christology' have been contested, and a majority of scholars argue that this 'High Christology' existed already before the writings of Paul. This 'incarnation Christology' or 'high Christology' did not evolve over a longer time, but was a 'big bang' of ideas which were already present at the start of Christianity, and took further shape in the first few decades of the church, as witnessed in the writings of Paul. According to Ehrman, these two Christologies existed alongside each other, calling the 'low Christology' an 'adoptionist Christology, and 'the 'high Christology' an 'incarnation Christology.' Adoptionist theology may also be reflected in canonical epistles, the earliest of which pre-date the writing of the gospels. The letters of Paul the Apostle, for example, do not mention a virgin birth of Christ. Paul describes Jesus as 'born of a woman, born under the law' and 'as to his human nature was a descendant of David' in the Epistle to the Galatians and the Epistle to the Romans. Many interpreters, however, take his statements in Philippians 2 to imply that Paul believed Jesus to have existed as equal to God before his incarnation. The Book of Hebrews, a contemporary sermon by an unknown author, describes God as saying 'You are my son; today I have begotten you.' (Hebrews 1:5) The latter phrase, a quote of Psalm 2:7, could reflect an early Adoptionist view. The 2nd-century work Shepherd of Hermas may also have taught that Jesus was a virtuous man filled with the Holy Spirit and adopted as the Son. While the Shepherd of Hermas was popular and sometimes bound with the canonical scriptures, it didn't retain canonical status, if it ever had it.