There is a special way to observe Chanucah in times of danger.

In normal times, the element of public display is essential to the act of lighting Chanucah candles. The halachah tells us to place the lights at the entrance to our homes so that they can be seen from the street. If we live on an upper floor, the lamps should sit next to the window, where they are visible to passers-by. The time to light candles is "until people cease walking in the market place". When there is no longer anyone around to see, the purpose of lighting candles is vitiated. The Talmud calls this integral, out-and-proud aspect of Chanucah candle-lighting pirsumei nisa, publicising the miracle. It is somehow necessary that the world be made aware of what happened on Chanucah and why it is still meaningful to the Jewish people.

One may ask, however, why publicity is not similarly essential to other holidays that memorialise miracles such as Purim or Pesach. Why does the halachah not insist that we decamp to the street to eat matzah or hamantaschen?

It seems that there is something inherent in Chanucah that requires public observance. If we probe the meaning of the holiday, we can readily see why. Chanucah celebrates the persistence of Judaism in the face of the dominant Hellenist culture of the Seleucids that tried to shut down Jewish observance, enforce cultural conformity and subjugate all to the ways of the majority. In facing down this oppression, the Hasmoneans ensured the continuation of the Torah's unique ideas, values and patterns of life.

When we observe Chanucah in a way that is publicly and distinctively different from what other people are doing, we continue the Jewish people's commitment to being who we are even if we are a small minority.

Organised Jewish life in Europe takes place behind barbed wire and CCTV cameras

The rabbis recognised, however, that there is a difference between healthy pride and suicidal recklessness. You don't have to endanger your life for pirsumei nisa. So they stipulated that "in times of danger one may place the lights on one's table inside and that suffices" (Talmud Shabbat 21b). What constitutes a time of danger? Rashi suggested that this condition referred to an idolatrous Persian festival in talmudic times that included lighting candles and did not like the competition offered by Chanucah lights. Tosafot and most of the other commentators disagree with Rashi, however, and understand "times of danger" more globally as referring to any period when the observance of the mitzvot is perilous because it is outlawed by the authorities.

Are we in "times of danger"? Clearly not in the sense that most of the commentators understood it. We are blessed to live in open, pluralistic, societies whose presidents and prime ministers, far from outlawing Chanucah, host ecumenical candle lighting ceremonies at their official residences. Yet there are dangers - real physical dangers - as well as the real fears that attend them.

Islamist terrorists in Europe kills Jews because they are Jews. They also kill cartoonists and journalists for criticism of Islam that the terrorists find upsetting and in Paris last month murdered 130 innocent people because they were out having fun on a Friday night. In the shadow of this threat, organised Jewish life in Britain and the rest of Europe takes place behind barbed wire and CCTV cameras in secured sites frequently guarded by police in flak jackets who are armed with automatic weapons.

The statistical dangers are small, but the precautions that are, correctly of course, taken to protect us are massive. Has anyone studied what it does to us and our children inside when we see that our schools and shuls and social centres are fortified compounds defending against people who want us dead just for being in those places?

Only part of the point of terror consists in killing people. Another purpose is to terrorise the living. It's meant to give the cartoonists or op-ed writers pause to consider whether they really want to express their opinions about Islam in quite so conspicuous and forthright a fashion. It intends to make Jews think twice about whether they go to that class at the shul, enrol their kids in the school, publicly identify as Jewish, remain in this country or continue to be Jews.

Chanucah comes to remind us of our enduring responsibility to project the light and the values of Judaism to the world beyond our community. Sometimes this can be scary and even dangerous. What counts as dangerous is a question for the admirable CST. I am certainly in no position to say whether, in a given area of London or Manchester, lighting a menorah outside your door will risk someone heaving a brick through your front window, or worse.

At a time of danger, the halachah says, it is sufficient to place the lights on one's table inside the home. The great 19th-century Chasidic Rebbe Rabbi Zadok of Lublin explained this to mean that at a time of danger when the light cannot brighten the darkness of the world, it must at least brighten the interior of your soul. When we light and nurture the inner spiritual light, it will eventually radiate outwards and we commit to work towards a world in which " out of Zion shall teaching go forth, and the word of God from Jerusalem".