The discussion over fictitious quotes reminded me of an old Jewish joke about a lawyer summoning a Rabbi to be a character witness:
Before summoning the rabbi to the witness stand, the lawyer, it is reported, approached the judge and said, “Your honor, the rabbi who is about to testify has an impeccable reputation among his fellow Jews. They tell a story that one day he came home and saw a thief rummaging through his living room. The frightened thief climbed out a window and ran off with some of the rabbi’s possessions, and the rabbi ran after him, shouting, ‘I declare all my property ownerless,’ so that the thief would not be guilty of having committed a crime.”
The judge looked at the lawyer skeptically. “Do you believe that story really happened?”
“I don’t know, your honor,” the lawyer answered, “but they don’t tell stories like that about you and me.”
[From Hillel: If Not Now, When?]
In other words, even when we’re pretty sure that the stories about Jesus are not historically accurate, perhaps we can still believe that they attest to his character. We can’t know that he ever said anything ever attributed to him, but we can believe that early Christians heard the saying and thought, “That sounds like something Jesus would have said …”
Of course, the question becomes whether or not we can make that leap. We know that there were proxy battles between different factions within the early movement. Maybe it’s not what Jesus would have said, but it’s what Mark/Matthew/Luke wanted him to have said, or believed that he would have said.