Why Do We Celebrate Hanukkah?

1 Maccabees 4:34-35 (mid-late 2nd century BCE)
34 Then both sides attacked, and there fell of the army of Lysias five thousand men; they fell before them. 35 When Lysias saw the rout of his troops and observed the boldness that inspired those of Judas and how ready they were either to live or to die nobly, he withdrew to Antioch and enlisted mercenaries in order to invade Judea again with an even larger army.

2 Maccabees 8:5-7, 24-26 (mid-late 2nd century BCE)
5 As soon as Maccabeus got his army organized, the nations could not withstand him, for the wrath of the Lord had turned to mercy. 6 Coming without warning, he would set fire to towns and villages. He captured strategic positions and put to flight not a few of the enemy. 7 He found the nights most advantageous for such attacks. And talk of his valor spread everywhere... 24 With the Almighty as their ally, they killed more than nine thousand of the enemy and wounded and disabled most of Nicanor’s army and forced them all to flee. 25 They captured the money of those who had come to buy them as slaves. After pursuing them for some distance, they were obliged to return because the hour was late. 26 It was the day before the Sabbath, and for that reason they did not continue their pursuit.

48 They also rebuilt the sanctuary and the interior of the temple, and made holy the courts… 52 Early in the morning on the twenty-fifth day of the ninth month, which is the month of Kislev… 53 they rose and offered sacrifice, as the law directs, on the new altar of burnt offering that they had built. 54 At the very season and on the very day that the Gentiles had profaned it, it was dedicated with songs and instruments. 55 All the people fell on their faces and worshiped and blessed Heaven, who had helped them. 56 So they celebrated the dedication of the altar for eight days, and joyfully offered burnt offerings...

5 It happened that on the same day on which the sanctuary had been greatly disrespected by the foreigners, the purification of the sanctuary took place, that is, on the twenty-fifth day of the same month, which was Kislev. 6 They celebrated it for eight days with rejoicing, in the manner of the festival of booths [Sukkot], remembering how not long before, during the festival of booths, they had been wandering in the mountains and caves like wild animals. 7 … they offered hymns of thanksgiving to Him who had given success to the purifying of his own holy place.

2 Maccabees 1:1, 7-9, 18
1 The Jews in Jerusalem and those in the land of Judea, to their Jewish kindred in Egypt... 7 In the reign of Demetrius, in the one hundred sixty-ninth year, we Jews wrote to you, in the critical distress that came upon us in those years after Jason and his company revolted from the holy land and the kingdom 8 and burned the gate and shed innocent blood. We prayed to the Lord and were heard, and we offered sacrifice and grain offering, and we lit the lamps and set out the loaves. 9 And now see that you keep the Festival of Booths in the month of Kislev, in the one hundred eighty-eighth year.... 18 Since on the twenty-fifth day of Kislev we shall celebrate the purification of the temple, we thought it necessary to notify you, in order that you also may celebrate the Festival of Booths and the fire given when Nehemiah, who built the temple and the altar, offered sacrifices.

What is Hanukkah? For our Rabbis taught: On the twenty-fifth of Kislev [begin] the days of Hanukkah, which are eight on which mourning for the dead and fasting are forbidden. For when the Greeks entered the Sanctuary [of the Temple], they messed up all the oils there, and when the Hasmonean dynasty [Maccabees] prevailed against and defeated them, they searched, and found only one portion of oil which had the seal of the High Priest, but which contained enough for one day’s lighting [of the Menorah] only; yet a miracle happened there and they lit [the lamp] with it for eight days. The following year these [days] were appointed a Festival with [the recital of] Hallel and thanksgiving.

With regard to the dates of these festivals, the Sages taught: When Adam the first man saw that the day was getting smaller bit by bit, as the days become shorter from the autumnal equinox until the winter solstice, he did not yet know that this is a normal happening, and therefore he said: Woe is me; perhaps because I sinned the world is becoming dark around me and will ultimately return to the state of chaos and disorder before creation… Once [Adam] saw that the season of Tevet, i.e., the winter solstice, had arrived, and saw that the day was progressively lengthening after the solstice, he said: Clearly, the days become shorter and then longer, and this is the order of the world. He went and observed a festival for eight days. Upon the next year, he observed both these eight days on which he had fasted on the previous year, and these eight days of his celebration, as days of festivities.

12:17 So Holofernes said to her, “Have a drink and be merry with us!” 18 Judith said, “I will gladly drink, my lord, because today is the greatest day in my whole life.” 19 Then she took what her maid had prepared and ate and drank before him. 20 Holofernes was greatly pleased with her, and drank a great quantity of wine, much more than he had ever drunk in any one day since he was born.

16:18 When they arrived at Jerusalem, they worshiped God. As soon as the people were purified, they offered their burnt offerings, their freewill offerings, and their gifts. 19 Judith also dedicated to God all the possessions of Holofernes, which the people had given her; and the canopy that she had taken for herself from his bedchamber she gave as a votive offering. 20 For three months the people continued feasting in Jerusalem before the sanctuary, and Judith remained with them.

16:31 The day of the celebration of this victory was put as a holiday in the calendar, and was celebrated by the Jews from that time up to the present.

Tosafot on Babylonian Talmud Megillah 4a (12th century CE)
Since women too were included in that miracle. Rashbam explained, that the primary part of the miracle was done by them; Purim - by Esther, Chanukah - by Judith, Pesach - for they were saved in the merit of the righteous ones of that generation.

Ran on Babylonian Talmud Shabbat 10a (14th century CE)
Since women too were included in that miracle. As the Greeks commanded that all the maidens who were married be carried off to the general first, and by a woman was the miracle done: as it is written in a midrash, Yochanan's daughter fed the leader of the Greeks cheese to get him drunk, and she cut off his head and escaped; and because of this it's customary to eat cheese on Hanukkah.

Josephus, Jewish Antiquities 12.324-326 (late first century CE)
So much pleasure did they find in the renewal of their customs and in unexpectedly obtaining the right to have their own service after so long a time, that they made a law that their descendants should celebrate the restoration of the temple service for eight days. And from that time to the present we observe this festival, which we call the festival of Lights, giving this name to it, I think, from the fact that the right to worship appeared to us at a time when we hardly dared hope for it.

Picture of menorah in the window of Rachel and R' Akiva Posner, 1932, Kiel:​​​​​​​

Peter Yarrow, "Light One Candle"
Light one candle for the Maccabee children
With thanks that their light didn't die
Light one candle for the pain they endured
When their right to exist was denied
Light one candle for the terrible sacrifice
Justice and freedom demand
But light one candle for the wisdom to know
When the peacemaker's time is at hand

Debbie Friedman, "Not by Might"
Not by might and not by power
But by spirit alone shall we all live in peace
The children sing, the children dream
And their tears may fall, but we'll hear them call
And another song will rise
Another song will rise, another will rise

Woody Guthrie, "The Many and the Few"
Eight candles we’ll burn and a ninth one too
Every New Year that comes and goes
We’ll think of the many in the hands of the few
And thank God we are seeds of the Jews