Some versions of the Jesus Myth Theory attempt to argue that Jesus was a sun god and that he was derived from other sun gods. But other than a desire to connect Jesus with Horus and other sun gods, is there any evidence that Jesus was originally conceived as a sun god? Later Christian artwork that portrays Jesus as having a halo does not speak to what the first Christians believed or wrote about.
Mark, the earliest Gospel, speaks of light twice (Mark 4:22; 13:24) but does not use it to describe Jesus. Matthew and Luke use light in a rather ordinary way and when it is used as an image, it for the Church and not Jesus.
The one possible exception is Jesus’ transfiguration, where Jesus’ face shines with the light of the sun (Matthew 17). The description of his face comes across as a minor detail with the focus being on the Father’s testimony about the Son. Besides, the description is fairly typical of heavenly beings. In addition, the earlier version in Mark 9:3 does not mention the sun or his face but rather describes the whiteness of his clothes.
Regarding the sun, Jesus uses it in a normal manner, except when he uses Old Testament allusions about the sun going dark at the Day of the Lord. These were images that were already present in Jewish eschatological thought.
Mythicists love John because there is much talk of Jesus as light. The question is, does the light imagery refer to the sun? It should be noted that John does not use the word ‘sun.’ Could it be assumed that light is equivalent to the sun? The early chapters contain a strong correspondence to the Genesis creation story (see this article I wrote). Light is the first thing created by God but the sun comes later. The Genesis account seems to be a direct response to pagan sun worship. John echoes this.
Paul only mentions the sun twice, neither in reference to Jesus. He speaks of light, but by far he uses light as a metaphor for truth rather than speaking of Jesus. If Jesus was originally a sun god, Paul seems unaware of this.
Why is it that most (all?) New Testament scholars neglect to comment on Jesus as a solar deity? It is most likely because if a person was not looking for it, they would never find these themes in the New Testament. Things like connecting Jesus to the sun because he was born on the winter solstice are meaningless, since the New Testament never says when he was born. If mythicists want to connect Jesus to pagan gods, they best look elsewhere.
For more information the Jesus Myth, get my book Unmasking the Jesus Myth.