So apart from the Liar/Lunatic/Lord trilemma, there is the option "A cult leader that didn't really claim the be the Lord, but his followers came to believe that he was".
I'm curious, what are this position's ideas on how his followers came to believe this? One common response to the general argument is that most of Jesus' disciples were martyred and would have had no motivation to die for a lie.
An important transformation is that the title of Messiah (or Christ in Greek translation) has a very specific meaning in a Jewish context, as a human king or savior of the Hebrew people. When early Christianity spread beyond Jews, this context disappeared, and the title "son of God" got reinterpreted in a Greek context, where gods could literally have children.
The Nicene Creed is one of the clearest statements of the "Jesus is God" hypothesis, but (as I said elsewhere in this thread) there are plenty of strong claims made in the gospels themselves. There are also similar claims made in many of the earlier writings of the church (if you're honestly interested, there are 10 pre-Nicene volumes at http://www.ccel.org/fathers.html .)
Not how the "witnesses" changed their beliefs and how they talked about what happened over time. Even though some of them came to distrust Joseph Smith or consider him on a wrong path, once they had convinced themselves they had seen something miraculous happen they had a hard time letting go.
They later made comments that suggested they had seen the things "in a vision" (yet most people assume an actual witnessing), the important consideration is to them it was real, and just as valid as actually seeing it. In their mind there was no difference - so they had no problem claiming they saw it first hand.
Faith is a type of insanity, so naturally you can't use the assumption of faithful people acting rationally (no motivation to die for a lie) to find truth.
As to how they came to believe it, again look at other religions, spiritual practices etc. It's quite common for followers/believers to come to believe something the leader is not saying - it has to be so, that's HOW IT WORKS.
It's similar to snake oil salespeople today like Deepak Chopra - you just make a lot of hand wavy claims about energy and quantum physics and people inject their own meaning.
Put these in a time period when education and access to information was low and et voila.
That's what I'd class as 'legend'.
For example, early in the gospel of Matthew, Jesus quotes the Old Testament saying "You are to worship the Lord your God and serve only him." At the very end of Matthew, Jesus meets the disciples, who worship him, and he does not criticize them or stop them (contrast with Peter in Acts 10.) Once that connection is made, it's an obvious divinity claim -- but it's one that might take time to realize is there.
A few other examples: Psalm 103 says the Lord "is the one who forgives all your sins"; Jesus does it in Mark 2. Both Isaiah 43 and Hosea 13 specify that God alone is Savior, and Luke 1:47 repeats it just prior to calling Jesus the Savior in Luke 2:11. Deuteronomy 10 establishes heaven as entirely God's property, but Jesus claims to be the one controlling entry to heaven in Matthew 7.
Given Jesus' obviously strong knowledge of the Hebrew scriptures, it's hard to get away from the conclusion that he was making intentional claims of being God.
That is not a very charitable interpretation of my comment.
I don't draw the conclusion because I want to. I draw the conclusion because I've studied the texts in great detail.
> "Jesus states that he hands Peter the keys to heaven, which following this logic then turns Peter into God."
Only if you haven't studied the texts in great detail. If you have, you'll recognize the parallel to Isaiah 22 -- Eliakim taking over Shebna's role, not as king, but as palace administrator. That's very different from the role Jesus claims in Matthew 7.
> "Jesus instructs his followers to forgive sins, which according to your logic turns them all into God."
Again, you're missing some nuance. The Lord's Prayer mentions forgiving sins "against us". I can forgive sins against me and you can forgive sins against you. In Mark 2, Jesus claims to forgive sins against God, which is why the crowd considers it blasphemous.
Again, these sorts of claims permeate all four gospels. They're things that, if you have a thorough grasp of the Old Testament, jump out of the text. But if you're not that interested in the details, you might totally miss it (and, to reverse your uncharitable take on my position: if you have already decided Jesus makes no divinity claims, you can surely rationalize it all away.)
The ambiguity might very well be intentional on the part of Jesus, since outright claiming to be the Messiah would be extremely dangerous - this would be equivalent to announcing a rebellion against the Romans.
But I'm totally convinced that he didn't claim he was Yahweh himself, that would have been ridiculous!
The passages you refer to are also pretty ambiguous, for example saying "Son, your sins are forgiven" does not necessarily mean that Jesus is the one forgiving the sins, it could also mean he informs the person that his sins have been forgiven by God.
Keep in mind the Lord-Liar-Lunatic argument is aimed at those who claim "Jesus is a great moral teacher" based on the things Jesus is quoted as saying. Jesus is quoted as making divinity claims, many of which are obvious if you have good knowledge of Hebrew scriptures and religious practices. The "Legend" option (Jesus didn't really say those things) is still open, but that makes it harder to claim anything about the value of Jesus' moral teachings.
The claim in Matthew 7 is much more explicit to modern readers -- Jesus is discussing how people will get into heaven or not based on his say-so.
So the 'legend' position would be "There was a heretical Judean Jew named Joshua son of Joseph who may well have given a sermon on some mount and was very likely crucified, but beyond that we are in no position to say anything. It's been too long, the records are too poor, and too many people with motivation to lie have had a chance to spread tales."
Why were there martyrs to begin with? Well, why did people drink the poison at Jonestown?