Contradiction with John 6:38
This verse describes Jesus saying He came down from heaven, whereas Mark 1:9 describes Him coming from Nazareth, which could be seen as a contradiction in His origin.
John 6:38: For I came down from heaven, not to do mine own will, but the will of him that sent me.
Contradiction with Luke 2:39
This verse implies that Jesus was brought up in Nazareth since childhood, while some interpret Mark 1:9 as His initial coming from Nazareth as an adult to be baptized, creating a seeming contradiction in His movements.
Luke 2:39: And when they had performed all things according to the law of the Lord, they returned into Galilee, to their own city Nazareth.