They began with the premise that He was not the Son of God, but merely a wise teacher. Then, they ruled out anything that indicated Christ claimed He could perform miracles, and anything that indicated people might go to Hell. Once they had it down to "Judge not lest ye be judged" and a couple of other phrases that reduced the Lord to being a doe-eyed hippie that said nothing more controversial than "be nice", they felt they had the true teachings of Jesus.
Sort of reminds me of how upset the secular crowd got about The Passion Of The Christ, because it focused mostly on His death, and not enough on the teachings of Jesus of Nazareth, philosopher.