For popular historians, Jesus as a myth is not taken very seriously. We have more evidence for the existence of Jesus Christ then almost any other historical figure from the time period. It is important to note that the arguments I am presenting in no way, shape or form reflect my opinion on this subject.
When I talk about Jesus as a myth, I simply mean that Jesus never existed. Even if He did exist, it would have no effect on the validity of Christianity. It is what Jesus did during his life, and the historical resurrection that is important. But we will not be discussing that here.
People try to dispute the existence of Jesus by arguing two things: the reliability of the gospels, and the reliability of non-Christian sources. The most popular way to dispute these is to use the word ‘hearsay’. Hearsay attempts to show that all sources pointing to the existence of Jesus are unreliable.
If you do not understand this, imagine yourself confronted with a charge for a crime which you know you did not commit. You feel confident that no one can prove guilt because you know that there exists no evidence whatsoever for the charge against you. Now imagine that you stand present in a court of law that allows hearsay as evidence. When the prosecution presents its case, everyone who takes the stand against you claims that you committed the crime, not as a witness themselves, but solely because they claim other people said so. None of these other people, mind you, ever show up in court, nor can anyone find them.
Jesus mythicists primarily use this to attack the gospels. Like the writings of Paul, James, John, and Peter. They conclude that since none of them ever mention seeing an ‘earthly’ Jesus, their evidence can only count as hearsay. They also use it against Josephus, Tacitus, Pliny the Younger, and others. It is true that no historian recorded Jesus while he was alive, and all non-Christian sources were born after His alleged death.
 – I would like to thank this source for the example of hearsay. It is also a great article if you are interested in further reading.