by One of the assumptions about a literary origin for the Jesus figure is that it would be invented all at once on a rainy afternoon, which it seems McGrath and the host (Elliot Saxton) dive into at the beginning. They find the many contradictions among the gospel narratives and attempts to shoehorn Jesus into scriptural prophecies to be awkward, and that this is an especial problem for 'mythicism'. I don't know that anyone is arguing it was made up by one person who had a concern for internal consistency - and even if such a person was found arguing that line it is not necessary for a Jesus who only exists in literature.
About a half hour in they make the case that the Historical Jesus is a better weapon against conservative christianity than a Jesus who never existed because it's a 'consensus' view more likely to garner respect. Maybe some folks thing being a better weapon is a reason to believe something, but for myself I am more interested in what happened.
They go on to suggest no 'actual scholars' seriously consider that Jesus didn't exist, then relent and admit some do. The idea is that it's safe to go with a majority, but who makes up this majority is more implied than specified. It should be obvious that being in the minority opinion doesn't imply being in the wrong either.
Most of the talk is vague handwaving about 'mythicists will say this' and 'mythicists say that' without directing the audience to who in particular, which might help us understand what the full argument might be. It would be helpful to be more specific, like "Dr X says in this paper that..." in order to make clear what the problem might be and how the counterargument resolves the issue.
There follows some discussion of interpolations. Not exactly sure how this is a special problem for 'mythicists' as it's just a problem with early christian texts anyone examining as evidence one way or the other. If the charge is that mythicism requires certain passages be interpolations it would be best to look at who makes the claim, what exactly is the claim, what evidence and arguments to they bring forward to advance their position.
At about the 40 minute mark they joke about a lost hypothetical document that 'mythicists' will conjure up (apparently trying to refer to Richard Carrier), which again would be useful to know where the claim is that this material is in a hypothetical document.
Around 50 minutes in McGrath concedes it is possible there was no 'historical Jesus' and admits Dr Carrier using Bayes' Theorem to organize thinking is a good and useful thing.
We also get a reference to 'the Brother of The Lord' interpretation.
Towards the end McGrath seems to argue against trying to sort out what is meant by very likely, most likely, likely, not likely etc. Which seems to me that would be useful to avoid being so vague that it's difficult to parse what is being said.
The proximity in time between the writing of christian literature and the putative time of an historical Jesus is mentioned as a problem for mythicism.
There was also discussion toward the end about polemics, which was somehow related to the 'criterion of embarrassment'.
At the very end McGrath says that if he did come out with a mythicist theory he would be showered with honors and money. I certainly don't see those who have already published on mythicism garnering these amazing benefits.
Overall it seemed like I didn't really have anything to learn as this was a conversation between two people who are in agreement and their dialog was too vague to be a benefit to a third party listening in.
