חמשה דברים אירעו את אבותינו בשבעה עשר בתמוז וחמשה בתשעה באב
בשבעה עשר בתמוז 1. נשתברו הלוחות 2. ובטל התמיד 3. והובקעה העיר. 4. ושרף אפוסטמוס את התורה 5. והעמיד צלם בהיכל
בתשעה באב 1. נגזר על אבותינו שלא יכנסו לארץ 2. וחרב הבית בראשונה 3. ובשניה 4. ונלכדה ביתר 5. ונחרשה העיר
Five bad things happened on the seventeenth of Tammuz, and five other disasters happened on the Ninth of Av.
On the seventeenth of Tammuz, 1. the luchot were broken by Moshe when he saw that the Jews had made the golden calf; 2. the daily offering was canceled by the Roman authorities and was never sacrificed again; 3. the city walls of Jerusalem were broken through; 4. the general Apostemos publicly burned a Torah scroll; 5. and Menashe placed an idol in the Sanctuary.
On the Ninth of Av 1. it was decreed upon our ancestors that they would all die in the wilderness and not enter Eretz Yisrael; 2. and the Beit Hamikdash was destroyed the first time, in the days of Nebuchadnezzar, and 3. the second time, by the Romans; and 4. Beitar was captured; and 5. the city of Jerusalem was plowed, as a sign that it would never be rebuilt.
But why should we care???
אקמצא ובר קמצא חרוב ירושלים... אקמצא ובר קמצא חרוב ירושלים דההוא גברא דרחמיה קמצא ובעל דבביה בר קמצא עבד סעודתא אמר ליה לשמעיה זיל אייתי לי קמצא אזל אייתי ליה בר קמצא אתא אשכחיה דהוה יתיב אמר ליה מכדי ההוא גברא בעל דבבא דההוא גברא הוא מאי בעית הכא קום פוק אמר ליה הואיל ואתאי שבקן ויהיבנא לך דמי מה דאכילנא ושתינא אמר ליה לא אמר ליה יהיבנא לך דמי פלגא דסעודתיך אמר ליה לא אמר ליה יהיבנא לך דמי כולה סעודתיך א"ל לא נקטיה בידיה ואוקמיה ואפקיה אמר הואיל והוו יתבי רבנן ולא מחו ביה ש"מ קא ניחא להו איזיל איכול בהו קורצא בי מלכא אזל אמר ליה לקיסר מרדו בך יהודאי א"ל מי יימר א"ל שדר להו קורבנא חזית אי מקרבין ליה אזל שדר בידיה עגלא תלתא בהדי דקאתי שדא ביה מומא בניב שפתים ואמרי לה בדוקין שבעין דוכתא דלדידן הוה מומא ולדידהו לאו מומא הוא סבור רבנן לקרוביה משום שלום מלכות אמר להו רבי זכריה בן אבקולס יאמרו בעלי מומין קריבין לגבי מזבח סבור למיקטליה דלא ליזיל ולימא אמר להו רבי זכריה יאמרו מטיל מום בקדשים...
The Gemara explains: Jerusalem was destroyed on account of Kamtza and bar Kamtza. There was a certain man whose friend was named Kamtza and whose enemy was named bar Kamtza. He once made a large feast and said to his servant: Go bring me my friend Kamtza. The servant went and mistakenly brought him his enemy bar Kamtza. The man who was hosting the feast came and found bar Kamtza sitting at the feast. The host said to bar Kamtza. You are my enemy. What do you want here? Get up and leave. Bar Kamtza said to him: Since I'm already here, let me stay and I will give you money for whatever I eat and drink. Just do not embarrass me by sending me out. The host said to him: No, you must leave. Bar Kamtza said to him: I will give you money for half of the feast; just do not send me away. The host said to him: No, you must leave. Bar Kamtza then said to him: I will give you money for the entire feast; just let me stay. The host said to him: No, you must leave. Finally, the host took bar Kamtza by his hand, stood him up, and took him out. After having been cast out from the feast, bar Kamtza said to himself: The Rabbis were sitting all there and did not protest the actions of the host, although they saw how he humiliated me. I will therefore go and inform against them to the king. He went and said to the emperor: The Jews have rebelled against you. The emperor said to him: Who says that this is the case? Bar Kamtza said to him: Go and test them; send them an offering to be brought in honor of the government, and see whether they will sacrifice it. The emperor went and sent with him a choice three-year-old calf. While bar Kamtza was coming with the calf to the Temple, he made a blemish on the calf’s upper lip. And some say he made the blemish on its eyelids, a place where according to us, i.e., halakha, it is a blemish, but according to them, gentile rules for their offerings, it is not a blemish. Therefore, when bar Kamtza brought the animal to the Beit Hamikdash, the Kohanim would not sacrifice it on the Mizbeach since it was blemished, but they also could not explain this satisfactorily to the gentile authorities, who did not consider it to be blemished. The blemish notwithstanding, the Sages thought to sacrifice the animal as an offering due to the imperative to maintain peace with the government. Rabbi Zekharya ben Avkolas said to them: If the priests do that, people will say that blemished animals may be sacrificed as offerings on the altar... As a result, they did nothing, bar Kamtza’s slander was accepted by the authorities, and consequently the war between the Jews and the Romans began.
So as we see here, baseless hatred, hating somebody and embarrassing them for no reason, is so destructive that it caused the destruction of the Beit Hamikdash!! But why should we be blamed for the sins of people 2000 years ago???
The Chofetz Chaim in his introduction to the laws of Lashon Hara says "The 2000 year old exile is not a continuous punishment for the sins of the people who lived in the time of the Second Beit Hamikdash! Hashem stands ready to end the exile immediately- were it not for the sins of Sinat Chinam and lashon hara which CONTINUE to cause destruction amongst our people.
One man spread a rumor about another. He later felt regret and went to the rabbi to ask how to make amends. “Go to the store and buy a pillow,” said the rabbi, “then go to a big open field and scatter the feathers of the pillow into the wind. Do so and report back to me in a week.”
The man did as he was told, and came back the next week to find out what to do next. “Now,” said the rabbi, “go back to the field and pick up all the feathers.”
“But,” the man protested, “those feathers have scattered far and wide! I’ll never find them all."
“Exactly,” explained the rabbi. “Now you understand. When we speak badly about another person, the effect is far and wide. And it is damage that can never be fully undone.”
Our tradition teaches that lashon hara can destroy many lives, even unintentionally, all in one:
Beware of the excuses children and adults often use for speaking lashon hara: