The historical evidence of Christ Jesus according to Harnack , a famous Lutheran theologian/philosopher could, at most, fit on less than a quarto page of script.
https://en.wikipedia.org/wiki/Adolf_von_Harnack
Consequent to mankind's progression into singular a materiality, or sense bound knowledge, the knowledge of the spirit was lost to mankind. Therefore the professors gleefully stripped Christ Jesus of any spiritual consideration and led modern man into only Jesus, the man, a high man, but man nonetheless.
Differences between gospels and lack of historicity , through their eyes, stripped the Divine, not only in man but all of nature into a scientific thought process of abject ponderability. The Protestant professors, especially, became scientific mountebanks in this movement into an ignorant materiality.
Aphoristically , at the Baptism by John in the 30th year of Jesus of Nazareth's life the Christ Being entered into Jesus of Nazareth and walked the earth for 3 years until the Event of Golgotha. In ancient times this might be considered that an Avatar came into the body of the man, Jesus, but yes, this event was beyond ancient perceptions as the Word, the Logos, entered into the man, Jesus, and subsequently died on the Cross.
Only mankind experienced Death to this time and the Creative God, Christ, went through Death as a Grand Cosmic Sacrifice. Subsequently The Christ Being entered into the Earth as the Spirit of the Earth into the hearts of ALL Men and works as an IMPULSE which is within Man unto his future, the future of further existence.
A Man works through his judgement, aided by the Christ Being as a template to the future of human kind. Mankind is only at the beginnings of the Christian Impulse which is in the inner activity of Man; consciously and subconsciously the human being realizes this Christ within and in this a new historicity is spiritually created.