One of the more salient critics of early Christianity was the pagan intellectual Celsus, who wrote his True Doctrine (sometimes translated as True Word) around 177-180 AD. Celsus actually took the time and effort to properly study Christianity in order to dissect it bit by bit. He did not uncritically repeat many of the wild rumors floating around about Christianity in his day and instead launched attacks where it would actually hurt, for he was not given to attacking straw men.
Celsus “was a man who relied not on rumors and hearsay evidence but on personal observation and careful study”. [Stephen Benko, Pagan Rome and the Early Christians (Bloomington, IN: Indiana University Press, 1986), 148.] The reason he did all this appears to be his genuine love for the Roman Empire, which he felt was being undermined. After reading Celsus, I actually have a begrudging respect for him and readily admit that some of his better arguments went unanswered by Christian apologists, even the illuminative Origen.
In a twist of history that would probably surprise both men, the only way we have Celsus’ True Doctrine preserved today is because Origen quoted Celsus at-length in his response work, Contra Celsum. What did Celsus say against Christianity? Maybe even more importantly for our purposes, what did he not say?
In Contra Celsum 2.6, we have this comment about the life of Christ: “Jesus kept all the Jewish customs”. Celsus said this in the course of an attack on Christian doctrine but it does show that Celsus was actually willing to use historical elements from the life of the historical Jesus against the Christianity of his day.
This was a clever tactic on his part and it helps us see if Jesus never existed at all, Celsus would have been more than willing to use that as well. Instead, he feels the praxis of Jesus stands in contradistinction to the praxis of Christians and this is his point of attack. In Contra Celsum 1.38, Celsus used more elements from the life of Jesus against the Christians: “…having tried his hand at certain magical powers he [Jesus] returned from there [Egypt], and on account of those magical powers gave himself the title of God”.
Here, Celsus refers to both the miracles and some of the (misconstrued) background of Jesus in a very real, albeit negative, way. Why did he not just say, “Your Messiah never even existed”?
In Contra Celsum 6.34, Celsus even mockingly confirms the death of Jesus as well as the method of said death: “If Christ had been thrown down a cliff or pushed into a pit, or strangled with a rope … then they would speak of a cliff of life, or a pit of resurrection, or a rope of immortality”. (Celsus said this in the course of making fun of Christian references to the cross as a glorious thing.) Furthermore, Celsus pointed out that the Christians would not worship Zeus because his tomb was right there in plain sight in Crete, yet their “god” was supposedly resurrected from his tomb.
Celsus, of course, did not believe in the resurrection and wondered why Christinas worshipped a dead man as immortal. Celsus felt that the whole doctrine of the resurrection was based on an incorrect interpretation of reincarnation. Either way, in his mind it was a decidedly disgusting and repugnant belief. Celsus chided the Christians for rejecting the traditional gods on one hand and then worshipping a mere man on the other hand. Worse yet, Celsus noted, was the fact that the man had lived recently: “If these men worshipped no other God but one, perhaps they would have a valid argument against the others. But in fact they worship to an extravagant degree this man who appeared recently” (Contra Celsum 8.12).
Celsus rejected the incarnation and accused the Christians of exalting Jesus the man to godhood status in order to ignore any real god – it was a sort of “Christological cop out”. To make matters worse, it was ludicrous in his mind that they thought this was consistent with any form of monotheism. If that is not bad enough, Celsus thought, this man was a convicted criminal who had been disgraced and executed. Besides, Celsus figured there were other men more worthy of worship than Christ anyway, such as some of the figures from ancient Greece. It is not hard to see why Celsus thought these were better candidates when he viewed Jesus, the lowly carpenter that he was, as “a pestilent fellow”, a liar, and a wicked sorcerer (remember Celsus claimed that Jesus learned magic while studying in Egypt).
Celsus did not reject everything in Christianity outright (e.g., the Logos doctrine, certain ethical principles) and he also had a fair share of criticism for the Jews and their Scriptures. In fact, Celsus mocked the Hebrew Scriptures because they seemed to be chock full of stupid myths and silly fables. This is important for us to note because Celsus never made a similar charge about the actual existence of Jesus.
In summary, Celsus never questioned the existence of Jesus although he had great suspicions about the alleged supernatural aspects to his life, such as the virgin birth story and all the fulfilled prophecies attributed to him – which is a much more sensible position to hold than that of the Christ as Myth thesis.