Christmas is a wonderful time. All over the western world thousands of happy people will gather in all our major towns and cities to watch the great annual switch on of the Christmas lights. There will be illuminated Christmas tress forming a glittering centrepiece to most of out main squares and all the main streets will be dripping with lights and sparkle. Stars and angels, reindeers and fantastic bells and baubles are all illuminated against the sky in wonderful feasts of light and colour.

In addition all of our cathedrals and many of our churches and public buildings will be beautifully illuminated with golden light. Their towers and facades brilliantly spotlit against the night sky.

Most of us will have a smaller Christmas tree in out own homes, alive with fairy lights or colour-changing LED lights, and many of us will have decorated the outside of our homes with cascades of white, blue or yellow icicles festooned around the eaves and gables. Some of us will even competing with the town centres by packing in as many light ornaments as we can, from illuminated snowmen and Santas to jolly elves and flying neon sleighs. Some of the private efforts are really magnificent, designed to attract visitors and collect money for charities.

It is no coincidence that Christmas occurs in mid winter, when the daylight hours are short and the nights are long and cold. Light has always been seen as a symbol of life itself. The sun is essentially a blazing ball of light and even the most primitive of men understood that it's warmth and light generated everything they needed to survive. When the bleak hours of darkness dominated their lives they needed to remind themselves and assure themselves that the brighter and warmer days would come again.

Pagan yule rituals celebrated the winter solstice when the days began to get longer, promising the return of the sun. Druid priests would cut the mistletoe from the sacred oaks to offer as blessings and burn bonfires of yule logs to banish evil spirits, conquer the darkness and welcome the light. It all helped to boost morale and promised good luck for the new year.

With the advent of Christianity much of the symbolism and substance of the these ancient rituals became incorporated into the new festive season of Christmas. Fixing the birth of Jesus on the 25th of December placed it close enough to the winter solstice for the celebrations to simply merge. Christmas is now the celebration of the birth of Jesus, but the birth of Jesus was marked by the star over Bethlehem which illuminated the spot and guided the shepherds and the wise men and so the symbolism of light was strengthened and maintained.

For centuries the celebrations were marked by the lights of bonfires and yule logs, by rush light torches, candles and the light of oil lamps. The Egyptians made the first candles with animal fat and later the Romans created wicked candles with beeswax. Candles are lit in the Catholic churches to symbolize Christ as the Light of the World, again stressing the symbolism of light.

Candles are also lit in remembrance of the departed. Candlelight processions at Lourdes create a moving river of candlelight. Candles and incenses sticks are lit at altars everywhere in every religion. In England at Christmas candlelight Carole services pack the churches.

The story of modern electrical Christmas lighting begins with Thomas Eddison in the United States of America in the 1980s. Eddison invented the first electric light bulb and displayed his invention by hanging strings of electric light bulbs around his laboratory in New Jersey. Later one of Eddison's employees used strings of electric light bulbs to decorate his Christmas tree in his home in Manhattan.

The idea was not an overnight success because those early lights were expensive and needed an electrician to install them. Gradually they were made safer and cheaper. The first Christmas lights to go on in London were lit up in Regent Street in 1954, and now of course they are everywhere. Modern technology creates the glittering pageants of light that we can now enjoy over the festive season of Christmas.

Recently the city of Norwich invested £300,000 to refurbish its array of Christmas lights. I have no other figures but that one is quite impressive. Electricity is not cheap and keeping the lights blazing through the whole of December and into the January sales is a huge commitment for councils and shopkeepers and everyone involved.

Christianity is not the only religion to display its faith and its hopes in glorious displays of light. Judaism has its own Festival of Lights in the Hanukkah, which is sometimes referred to as the Jewish Christmas because it can take place around the same time. The festival lasts for eight days and eight nights. On each day one branch is lit of the eight branched Hanukkah candelabra.

The festival celebrates the re-capture of Jerusalem during the Maccabees revolt of the second century BC. The traditional seven branch candelabra of Judaism, which also symbolizes the Tree of Life, was re-lit in the Holy temple, and the one available earthen pot of uncontaminated oil lasted for eight days. To celebrate that victory the Hanukkah candelabra now has one extra branch.

One of the most popular religious festivals of India is the Diwali, the five day Festival of Lights that is celebrated by Hindus, Jains and Sikhs. Diwali symbolizes the victory of good over evil, light over darkness and knowledge over ignorance. Houses, temples and workplaces are decorated with oil lamps and elaborate rangoli art designs of coloured sand and powders and flower petals. There is family feasting and the sharing of sweets and gifts.

The Lantern Festival of China has marked the end of the traditional new year celebrations since the time of the Han dynasty which began 200 years before Christ. There are many legends attesting to its origins but the most popular seems to be that with the growth of Buddhism the Emperor Ming ordained that everyone should follow the custom of the new Buddhist monks in lighting the lanterns on the fifteenth of the first calendar month.

Thailand and Taiwan also celebrate lantern festivals when thousands of yellow lanterns are released to sail up and fill the night sky with artificial light. A delightful variation of these light festivals is to sail candle lit paper boats across lakes or down rivers such as the Mekong in North Vietnam.

The religious significance of light is universal. In Genesis, the first book of the Bible, the first words of God are “Let there be light.” God sees only darkness and his first act is to create light to divide creation into darkness and light. In our popular Christmas carols we sing of the “Star of Wonder, Star of Light.” In The Little Town of Bethlehem we sing of the dark streets shining with everlasting light.

In Christian art angels are forms of light and all the saints and all those that are blessed are shown wearing haloes of light. Christ is often portrayed holding a candle to light the way and is described as the Light and the Life.

In Hinduism light symbolizes Brahman, the creative force and all forms of divinity, purity and supreme bliss. It can symbolize any heavenly body, the world of Brahman and the power of the sky, and the illumination of the human mind. In the Bagavad Gita, when the God Krishna appears to the prince Arjun, he is described as too brilliant for the human eye to behold.

Islam does not allow any representation of God but God can be understood and described as the Light of the Heavens and of Earth. The source of uncoloured light is the source of all things when it refracts. Mosque lamps of enamelled glass are a reminder of the Light verse in the Koran, a parable which defines the divine light as a lamp which will guide whom He wills to His Light.

Light as a guiding force appears not only in Christianity and Islam but in all religions. Not only in life but also in death. People who have survived near-death experiences always describe themselves as being drawn or directed to the light.

Even atheists have to believe in the power of light, for what was the Big Bang except a gigantic explosion of light which gave birth to all the brilliance of the stars and the galaxies that fill our universe. Science agrees with the Big Bang theory but the idea that science is necessarily opposed to religion is untrue. Theists can simply believe that the big bang was kick-started by God. The Big Bang and evolution are simply the tools with which God worked. There is no logical need for a division between God and science.

Light is life. Ask any biologist about the principles of photosynthesis.