"Rabbi Yochanan said, 'What is the meaning of the verse in The Book of "Mishlei" (Proverbs 28) which reads, 'Fortunate is the one who is always fearful, but the one who is hard of heart will suffer misfortune?' It was because of 'Kamtza and Bar-Kamtza' that Yerushalayim was destroyed "
"For there was a certain individual who was friendly with Kamtza, but who was an enemy of Bar-Kamtza. He made a feast and said to his servant, 'Go and bring Kamtza to my feast,' but the servant brought Bar-Kamtza instead."
"The one who made the feast found Bar-Kamtza seated there. He said to him, 'Since you are my enemy, what are you doing here? Get up and get out!' Bar-Kamtza said, 'Since I'm here already, let me stay, and I will pay you for what I eat and drink.' "
"The host responded, 'No!' "
" 'I will pay for half the cost of the feast.' "
" 'No!' "
" 'I will pay the entire cost of the feast!' "
" 'No!' And he seized Bar-Kamtza, stood him up, and threw him out!"
"Bar-Kamtza thought, 'Since the Rabbis were there, saw the whole thing, and did not protest, obviously they had no objection to my embarrassment! I'll go now, and have a little feast-of-slander with the king."
"Bar-Kamtza went to the Caesar and declared, 'The Jews have rebelled against you!' "
"The Caesar responded, 'Who said so?' "
"Bar-Kamtza said, 'Send them a sacrifice, and see if they will offer it.' "
"The Caesar sent (with Bar-Kamtza) a healthy, unblemished ram. While going, Bar-Kamtza caused a disfigurement in the animal. Some say that it was a blemish on the upper lip; others say that it was a blemish in the eye (perhaps symbolizing the silence of the rabbis, or their witnessing of the event of his disgrace without protest); in any case, a place where for us it is a disqualifying blemish while for the Romans, it is not."
"The Rabbis had in mind to sacrifice it anyway to maintain peaceful relations with the government. But Rabbi Zechariah son of Avkulos objected, 'People will say, 'Animals with blemishes may be sacrificed on the altar!' "
"The Rabbis had in mind to kill Bar-Kamtza so that he would not report what had happened to the Caesar! But Rabbi Zechariah son of Avkulos objected, 'People will say, 'One who makes blemishes in sacrifices is killed!' "
Rabbi Yochanan said, "The excessive carefulness of Rabbi Zechariah son of Avkulos destroyed our Temple, burned our Palace, and exiled us from our Land."
Additional significant events are recounted there in the Talmud, but these are enough to paint a picture of a group of Torah "scholars," the majority of whom had become corrupted such that the embarrassment of a human being was less important in their eyes than the offering of a sacrifice according to all the details of the Torah, and this was true in their eyes even when that would throw the whole nation into danger.
At the end of the section on the destruction of the Holy Temple, there is a statement by Rabbi Elazar, as follows, "Come and see what is the tremendous negative impact of embarrassing someone, for Hashem helped Bar-Kamtza and destroyed His House and burned His Palace."
Tiger at the Gates - The Approach of the Enemy and Famine in Yerushalayim