The first murder in history occurred on the 25th of Kislev in the year 41 from creation (3720 BCE), when Adam and Eve's eldest son, Cain, killed his younger brother, Abel, as recounted in the 4th chapter of Genesis.
Link:
Cain and Abel: The Story of the First Sibling Rivalry
Why Did Cain Kill Abel
The vessels, tapestries, wall sections and other components of the Mishkan (the portable sanctuary or "Tabernacle" built under Moses' direction to house the Divine Presence during the Israelites' journeys through the desert) were completed on the 25th of Kislev in the year 2449 from creation (1312 BCE). The Mishkan was not assembled, however, until 3 months later, when, beginning on Adar 25 of that year, it was erected and taken down daily for a 7-day "training" period prior to its dedication on the 1st of Nissan. Our Sages tell us that the day of Kislev 25 was compensated 12 centuries later, when the Maccabees dedicated the Holy Temple on Kislev 25, 3622 (139 BCE -- see below).
Links: The Mishkan described in the Torah and commentaries; from the Chassidic masters on the Mishkan
On the 25th of Kislev in the year 3622 from creation, the Maccabees liberated the Holy Temple in Jerusalem, after defeating the vastly more numerous and powerful armies of the Syrian-Greek king Antiochus IV, who had tried to forcefully uproot the beliefs and practices of Judaism from the people of Israel. The victorious Jews repaired, cleansed and rededicated the Temple to the service of G-d. But all the Temple's oil had been defiled by the pagan invaders; when the Jews sought to light the Temple's menorah (candelabra), they found only one small cruse of ritually pure olive oil. Miraculously, the one-day supply burned for eight days, until new, pure oil could be obtained. In commemoration, the Sages instituted the 8-day festival of Chanukah, on which lights are kindled nightly to recall and publicize the miracle.
Link: The Story of Chanukah
Kislev 25 is the yahrtzeit (date of passing) of Rabbi Chaim Chizkiah Medini (1832-1904), author of the Halachic encyclopedia Sdei Chemed.
Today is the first day of the eight-day festival of Chanukah. In commemoration of the miracle of the oil we kindle the Chanukah lights—oil lamps or candles—each evening for eight days, increasing the number of lights each evening.
In the Jewish calendar, the day begins at nightfall; thus, the first Chanukah light is kindled on the preceding evening, which is when the Hebrew date of Kislev 25 begins. Tonight is the eve of the 2nd day of Chanukah, so we kindle two lights in the Chanukah menorah.
The lights—which ideally should be kindled soon after sunset—must burn for at least half an hour after nightfall. Learn more about the proper lighting time.
Links:
Text and Audio of the Menorah Blessings
Additional Chanukah observances and customs are listed below:
Special prayers of thanksgiving -- Hallel (in its full version) and V'Al HaNissim -- are added to the daily prayers and Grace After Meals on all eight days of Chanukah. Tachnun (confession of sins) and similar prayers are omitted for the duration of trhe festival.
On Chanukah we eat foods fried in oil—such as latkes (potato pancakes) and sufganiot (doughnuts) -- in commemoration of the miracle of the oil.
It is also customary to eat dairy foods in commemoration of Judith's heroic deed.
It is customary to play dreidel—a game played with a spinning top inscribed with the Hebrew letters Nun, Gimmel, Hei and Shin, which spell the phrase Nes Gadol Hayah Sham, "a great miracle happened there." (It is said that when the Greeks forbade the study of Torah, Jewish children continued the study with their teachers in caves and cellars; when the agents of the king were seen approaching, the children would hide their scrolls and start to play with spinning tops...)
Links: How to Play Dreidel
It is an age-old custom to distribute gifts of Chanukah gelt ("Chanukah money") to children on Chanukah. (It was the custom of the rebbes of Chabad-Lubavitch to give Chanukah gelt to their children and other family members on the fourth or fifth night of Chanukah; more recently, however, the Lubavitcher Rebbe encouraged the giving of Chanukah gelt every day of the festival—except for Shabbat, when handling money is forbidden.)
Links:
Why the Chanukah Gelt?
Some people think that if they were truly spiritual, they would never eat.
In truth, few acts are as divine as eating food.
Eating is similar to sifting gold. You grasp the divine spark within a food and reject the dross. And then, in the mitzvahs energized by that food, you carry that divine spark back to its origin within the oneness of its Creator.
That is why there are foods that are forbidden and foods that are permissible. The Hebrew word for “forbidden” is assur—meaning tied down. “Permissible” is mutar—untied.
Kosher means “fit.” Foods that are assur are not fit for the divine act of eating because the divine spark within them is tied down and cannot be released. If we would eat them, rather than carrying that spark upward, we would be pulled down with it.
But foods that are mutar are fit and ready to release powerful divine energy into all the mitzvahs we do.