C.S. Lewis once made this response to people who claim Jesus was a great moral teacher but not a god:
“I am trying here to prevent anyone saying the really foolish thing that people often say about Him: I’m ready to accept Jesus as a great moral teacher, but I don’t accept his claim to be God. That is the one thing we must not say. A man who was merely a man and said the sort of things Jesus said would not be a great moral teacher. He would either be a lunatic — on the level with the man who says he is a poached egg — or else he would be the Devil of Hell. You must make your choice. Either this man was, and is, the Son of God, or else a madman or something worse. You can shut him up for a fool, you can spit at him and kill him as a demon or you can fall at his feet and call him Lord and God, but let us not come with any patronizing nonsense about his being a great human teacher. He has not left that open to us.”
This is referred to as the Lewis Trilemma, and is often shortened to the phrase “Lunatic, Liar, or Lord.” The basic premise being that Jesus cannot have been a great moral teacher and still been an ordinary human, because he also claimed to be God. If that claim was untrue, then he could only have been a liar or a madman, both of which would mean everything he has to say should be disregarded. A popular atheist response to this is that the trilemma is a false one, in that there exists a fourth ‘L’-word that could also be applied: Legend. The argument basically goes that Jesus, if he existed at all, was a dude who had valid moral lessons to teach, while his supernatural claims and/or abilities were legendarily attached to him as embellishments by the authors of his stories. And while I agree that this is a valid alternative, I kind of hold to a different view.
My view is that the Trilemma is nonsense from the outset. Quite simply, the whole argument rests on an assumption that we need not make in the first place: that the question of whether or not Jesus’ moral teachings have value is dependent in any way on his identity or character.
Let’s just take one example: the Golden Rule. Do unto others as you would have them do unto you. As a general rule, I think most of us can agree that this is a reasonably good one to apply in your life. But in evaluating the idea and how it might best be applied, does it really matter who said it? Does it matter whether that person held some delusion that he possessed supernatural ancestry? Does it matter whether he lied about his parentage? Does it matter whether every word he ever uttered in his entire life, except for that one sentence, was a complete fabrication? Absolutely not. Either it’s a good idea, or it’s not. It is the idea that we ought to evaluate and not the speaker.
That’s why I think the whole formulation of the Trilemma is misguided from its very core. If somebody convinces people that they really ought to be doing things that make other people’s lives better, and I am rationally convinced that these are good moral precepts, then I’m likely to call that person a good moral teacher regardless of how ridiculous any claims he might make about his nature and origin might be. I’m on board with giving medicine to the sick, for example, even if the person who convinced me to do so claims to be a lily pad, a god, a demon, or an alien from the planet Orgasmo. Those claims are irrelevant to the value of medicine.
To Lewis, though, it’s the claim of supernatural authority that is the only relevant part of the equation. Either Jesus really was a god, in which case everything he said is authoritative, or he wasn’t, in which case everything he said was a damnable lie or irrational insanity. It’s a paradigm in which the moral value of everything is dependent solely on whether it has supernatural authority behind it, as if there was no possibility of independently evaluating the impact and value of Jesus’ various statements and claims. To Lewis, it doesn’t matter how good or valuable anything Jesus had to say was; if he claimed to be God, and wasn’t, then he was leading people away from the real God. That makes him either evil or insane, and his teachings valueless.
I can even sort of get why that would be the case from his perspective. In many forms of Christianity, the only true good is to believe in, worship, and obey their god. Outside of that, nothing you do matters. But it’s an argument that, it seems to me, is silly to direct at anyone. With rare exception, Christians accept that Jesus really was God, and so they wouldn’t be making an argument that he was a great (but merely human) moral teacher. And most people who do think he was a great human moral teacher don’t think the value in his teachings comes from being a god. So what’s the purpose of the argument? I suspect, mostly, that it exists to reassure people who already believe in Jesus’ divinity that they should continue to do so.
But there’s no logical connection between Jesus being a literal god, and Jesus having some cogent things to say on the subject of morality.