I am well aware of Celsus and his spurious attacks on Jesus and the Christian faith, but, to be honest, I had not heard of the Toledot before. Technically, the Toledot is not part of the Talmud, by the way, but I will respond to this document anyway. I believe that we can totally discount the Toledot as having even a shred of historical usefulness, except perhaps as a reflection of anti-Christian sentiment among Jews in the early Middle Ages. The scholarly opinion is all over the map, but given that this document (really, a set of similar but varying documents) mentions Christian holidays which did not even exist until the fourth century all agree that it is a late document. There is not the slightest evidence in this document that the one who wrote it was trying to discover early sources with reliable information about what Jesus actually said or did. Opinions vary from the fourth century to a more likely sixth to eighth century for the earliest form of the Toledot being put together. This was merely an anti-Christian polemic which drew from earlier Jewish anti-Christian polemics and added other spurious details. So, as I said, even those who are enemies of Christianity, and even the discredited Robert Price do not have the gumption to claim that the Toledot has historical value with regard to what Jesus said and did. To summarize, this document is a useful record of anti-Christian polemics, but is has no value for assessing what Jesus said or did.
Celsus is the first important Greek philosopher to write an anti-Christian polemic that we know of. What he has to say is far more useful, not in understanding what Jesus said or did, but in understanding sentiment among Greek intellectuals at this formative stage in anti-Christian thought. The way I think about it, Celsus was aware of much or all of the New Testament, but he also did his own research to find what kinds of “dirt” were out there on Christianity. It would be kind of like a district attorney trying to put together the strongest case against Christianity he could muster from whatever sources were available. In other words, Celsus’ work is a polemical attack and he had no intention of fairly assessing the evidence in support of the central claims of Christianity.
So… Some details. Celsus wrote his polemic On the True Doctrine somewhere in the 170s AD. There is some reason to think that he may have had the work of Justin “Martyr,” the early Christian apologist in mind when he wrote. Origen, writing in the mid third century, quotes Celsus extensively in his work Against Celsus, so we can assume that we have a fairly good idea of what Celsus wrote. Because Origen, a brilliant writer and scholar, wanted to provide useful means to refute Celsus, we can assume he accurately quoted him. So, what did Celsus actually say? Origen tell us that Celsus claimed that some Jews said Jesus’ father was actually a Roman soldier named Pantera. I believe it is fair to say that no scholar takes this spurious story of Celsus, taken from Jewish enemies of Christianity, seriously. If it is anything at all, it is a record of the kinds of myths about Jesus purposefully invented in order to discredit the gospels and Christianity. There is no record of this invention of a Roman father before Celsus and it can be completely rejected as having any historical usefulness at all. To give an idea of the polemical nature of Celsus’ attack on Christianity, he calls them, ” a swarm of bats, or ants creeping out of their nest, or frogs holding a symposium round a swamp, or worms in conventicle in a corner of the mud. As to Celsus’ other arguments, he claims that Jesus did miracles, but that they were done by the power of the Devil, not by God. This is an argument that the Jews leveled against Jesus during his ministry, which Jesus deflected with ease, noting that, given that he drove out demons it was irrational to propose that he drove out demons by the power of demons. It is not a reasonable accusation against Christianity that Jesus walked on water or changed water to wine or raised Lazarus from the dead due to satanic or demonic power. in fact, if Celsus’ argument tells us anything, it is that it was well known in the mid-second century that Christians claimed and believed that Jesus worked great signs, and miracles. Celsus’ refutation falls flat, in my opinion, but you can decide for yourself.
Celsus also makes the claim that the Jewish scripture does not prophesy a messiah like Jesus. He claims that the Jewish expectation was for a strong leader to save them militarily from their enemies. We know that this is an accurate reflection of Jewish sentiment, both in the first century, as this sentiment is found in the New Testament and it has been a part of Jewish response to Christianity up to modern times. I believe that this charge is refuted by Isaiah 53 (prophecy of a suffering servant Messiah) and by Zechariah 11 (a prophecy that the Messiah would be betrayed for 30 pieces of silver) and by Psalms 22 (a prophecy that Messiah would be crucified). So, anyone who likes can evaluate this claim by Celsus, but it does offer us a glimpse into what we could perhaps call a legitimate debate about Christian claims in the second century. We will have to judge for ourselves if Celsus is right on this point.
Celsus claims that the current text of what we call the New Testament had been changed to make the story of Jesus appear more believable. What he did not do is produce any evidence that this is in fact true. So, here we have a charge with no evidence, and no evidence that he even had evidence. Again, we can judge for ourselves, because we have a lot of evidence for the reliability of the New Testament documents. If you are interested, I have a lot on this topic in my book Reasons for Belief (www.ipibooks.com)
Celsus’ main purpose in his book seems to be to oppose the Christian’s divisiveness. The fact that they would not take part in idolatrous Roman customs meant to Celsus that they were not good Romans. Again, this does nothing to undermine our confidence that the gospels are reliable records of what Jesus said and did.
This is a rather incomplete analysis of Celsus, to be honest, but my conclusion is that Celsus is a much more important source, by far, than the Toledot, but as far as I can tell, Celsus’ polemic against the Christians provides nothing more than a useful source on what the Greek philosophers’ response was to Christianity in the mid-to-late second century, but it does nothing to undermine the reliability of Christian texts written more than one hundred years before Celsus wrote his anti-Christian polemic. His claims of fact are spurious, and his attacks on the lifestyle of Christianity are merely his opinion about this group, and I suppose he was entitled to his opinion.
By the way, Celsus said other things, and this response, admittedly, is not complete. If you have specific claims of Celsus you want me to respond to, please feel free to send those more specific examples to me, but since you asked a somewhat open question, I have given an overview response.