Although the siege that was the beginning of the destruction of the Second Temple started on another date, since an earlier fast commemorating the siege that destroyed the First Temple and the Kingdom of Israel was ordained on the tenth of Tevet, the fast remained on this date. This fast also includes two other unfortunate events that occurred near that date, the death of Ezra the Scribe on the ninth of Tevet, and the translation of the Torah into Greek on the eighth of Tevet. The sages say about Ezra the Scribe that he was worthy of the Torah being given by him, had not Moses preceded him (Sanhedrin 21b).
He is considered second only to Moses. The sages also said that Ezra the Scribe who came from Babylon to build the Second Temple is the prophet Malachi (Megillah 15a). On one hand, he is the last of the prophets whose prophecy appears in the Bible; on the other hand he promulgated ten general ordinances, thereby being the first of the sages who wrote and taught the Oral Torah. He therefore was the Torah sage who was the link between the Written Torah and the Oral Torah. And like Moses, he was the leader who led all of Israel, and headed the immigrants from Babylon who rebuilt the Second Temple.
Years later, when the Greek kingdom ruled over Israel, they decreed that the Torah be translated to Greek. That day is considered as bitter as the day that the Jews made the Golden Calf. The reason why was because until then, the Torah belonged solely to the Jews, but when it was translated into Greek, it was no longer unique to the Jews, and it began to spread and every person could do with it what he wanted. This happened on the eighth of Tevet, and we fast over this unfortunate event on the Tenth of Tevet too.
Rabbi Zvi Yehuda Kook said that the tragedies that occurred on the 8th, 9th and 10th of Tevet should be rectified in these ways: 1) Corresponding to the siege of Jerusalem, we have to strengthen the walls and build the land spiritually and physically. 2) Corresponding to the death of Ezra, we have to increase Torah study and glorify it while engaging in bringing Jews back to Israel as Ezra did. 3) Corresponding to the Greek translation of the Torah, we have to restore the original Jewish spirit and culture, and uproot the foreign ideas that took root during the exile and under non-Jewish rule.
“For these I weep…” (Lamentations 1:16) “It was the ninth year of his reign in the tenth day of the tenth month that Nebuchadnezzar, king of Babylon, and all his army came to Jerusalem and encamped against it and they built works of siege around it. And the city came under siege until the eleventh year of King Zedekiah.” (Kings II 25:1-2) In the ninth year of King Zedekiah’s reign, Nebuchadnezzar, king of Babylon, or in the words of Chronicles, the king of the Chaldeans, came and lay siege to the city of Jerusalem. King Zedekiah is Mataniah son of Josiah who Nebuchadnezzar crowned as king over Judea instead of Joachin his nephew (but according Chronicles 36:10, he was his brother).
The king of Babylon trusted that the king of Judah would be loyal to him and would pay him tribute. He submitted for about four years and then decided to rebel — and also rebelled against G-d. He ordered his ministers to seize the prophet Jeremiah, and cast him into the prison courtyard (Jer. 37:21). King Zedekiah turned to the king of Egypt, the enemy of the king of Babylon, for help, but to no avail.
Jeremiah pleaded with him that the only way to save the kingdom of Judah and the rest of the people was by total surrender to the kingdom of Babylon. The king did not heed his call and continued in his rebellion against the king of Babylon (Kings II 24:20). The furious king of Babylon ordered his troops to lay a siege on Jerusalem after conquering most of Judah’s fortified cities (Jer. 34:7).
Nebuchadnezzar encamped on Jerusalem and laid siege to it. According to the Targum, he built lookout posts along the wall to know what was going on in the city under siege. On the ninth day of the fourth month, the inhabitants of besieged Jerusalem suffered from hunger and there was no more bread for the people or the fighters.
In the words of the Book of Lamentations: “All her people are sighing [as] they search for bread; they gave away their treasures for food to revive the soul.” (Lam 1:11), “They say to their mothers, ‘Where are corn and wine?’” (Ibid. 2:12) “Will women devour their own offspring, children that they caressed?” (Ibid. 2:20). The lack of bread and the ravages of starvation weakened the defenders of Jerusalem and then the Babylonians were able to break through the city walls.
By comparing Scripture, it seems that the city had two walls (“and all the ministers of Babylon came and sat at the gate in between…” — Jer. 39:3) but the extra fortifications didn’t help. King Zedekiah saw the Babylonian invasion and managed to sneak out at night and escape through the king's garden to the west. Zedekiah and his men decided to flee to one of the countries in Transjordan. He was known to have a good relationship with the Ammonites, Moabites and Edomites, as appears from the story of Gedaliah son of Achikam (Jer. 40:11-12).
The Babylonians pursued Zedekiah and his men and managed to catch them in the plains of Jericho. The Midrash relates that the King built himself an emergency underground tunnel and when he saw the Babylonian camp break through the walls of the city, he fled through the tunnel, hoping to save himself that way. But G-d made a deer run over the tunnel and the Babylonians, chasing after the deer, discovered King Zedekiah in the plains of Jericho and captured him.
The Babylonians took him prisoner, and the king ordered his sons slaughtered before his eyes, and then to blind him. The Midrash relates that Zedekiah asked the king of Babylon, “Kill me first so I won’t see the death of my ten sons”, while his sons asked the king, “Kill us first so we won’t see the blood of our father.”
The Babylonian King killed the sons first, and then gouged out Zedekiah’s eyes and brought him to Babylon. Zedekiah vindicated his punishment, “Jeremiah prophesied about me, ‘You shall go to Babylon and you shall die in Babylon, but your eyes will not see Babylon’ and I didn’t listen to him.” (Yalkut Shimoni on Kings II 25) We also find a reference to this prophecy in the words of the prophet Ezekiel: “And I spread my net and he will not see it, and he will die there.” (Ezekiel 18:12-13).
On the eleventh year of Zedekiah's kingdom, in the month of Av (July-August), Jerusalem was destroyed. Jerusalem had been under siege for a year and a half. In comparison, the city of Samaria, the capital of Israel, was under siege for about three years until it was destroyed. The Ten Tribes were exiled to Assyria in the days of King Hoshea ben Elah. (Kings II 17:1-7)
The Babylonians burned the king’s house and Nevuzaradan the army general exiled the rest of the people to Babylon. “And he exiled the survivors from the sword to Babylon, and they became vassals to him and to his sons until the reign of the kingdom of Persia.” (Chronicles II 36:20). The tenth of Tevet, the day when the siege began on Jerusalem, was decisive in the series of events that led to the fearful destruction of Jerusalem.
This day was declared a fast day as the prophet Ezekiel commanded: “Then the word of the Lord came to me in the ninth year, in the tenth month, on the tenth of the month, saying: “Son of man, write for yourself the name of the day, this very day; the king of Babylon has besieged Jerusalem on this very day.” (Ezekiel 24:1-2).
This day is one of the fasts which in the future will turn into days of joy, according to the words of the prophet Zechariah: 'So said the L-rd of Hosts: The fast of the fourth [month], the fast of the fifth [month], the fast of the seventh [month], and the fast of the tenth [month] shall be for the house of Judah for joy and happiness and for happy holidays — but love truth and peace. (Zechariah 8:19).
Sources: Kings II 25, Jer. 39, Jer. 52:4, Ezekiel 24:1, Zachariah 8, Chronicles II 36:10.