Angels at the square

Being in London during the Christmas season was a treat to begin with. Marzipanned Christmas cakes appeared in every baker's window. Alongside barrows of Israeli oranges and French apples the greengrocers were selling evergreen trees, and vendors hawked chestnuts from glowing curbside braziers. To me it all seemed very Dickensian indeed.

Best of all were the carolers who popped up everywhere, smiling and singing and holding out their charity collection boxes to the passing crowds of shoppers. I remembered how Scrooge had chased a young caroler from his door one fog-enshrouded Christmas Eve (''I don't make merry myself at Christmas and I can't afford to make idle people merry!''), and I always found a stray shilling to put in the box. God rest ye merry, gentlemen Let nothing you dismay . . .

In Trafalgar Square four huge bronze lions guard the base of the famous monument to Lord Nelson. At Christmas time they are joined by a life-size manger scene and a magnificent fir tree - a symbol of peace - given annually by the people of Norway. Beneath its branches is a temporary platform wired for sound, where local choirs sing carols every December evening until Christmas. Theatergoers, travelers and weary shoppers gather together in the square to listen and hum along.

One evening late in December I wandered into the Square, where the enormous lions now cradled loudspeakers between their sphinx-like paws. The first choir of the evening, a scraggly group of schoolchildren whose enthusiasm more than made up for their missed notes, was just completing its program. We wish you a Merry Christmas, We wish you a Merry Christmas, And a Happy New Year!

The next performers took a very long time to set up. A van from a local radio station had arrived and men were running cables over the lions, up to the platform - everywhere - to tape the carols for broadcast the following day.

''Excuse me,'' said a pretty young woman with a Scandinavian accent. ''Do you know when they will sing again?''

''Soon, I hope,'' I smiled at her. I felt an immediate affinity with someone else who was spending Christmas in a foreign country. We chatted while we waited , stamping our feet on the pavement to keep warm. She had come from Sweden to work in London and this was her first Christmas away from home.

''I like to sing the music of Christmas,'' she told me, ''but the English songs are not the same as in Sweden. I do not know them.''

I knew how she felt. The English had different tunes to carols familiar to me as an American, different words to others, and some of my favorite carols were completely unknown to them.

On the platform an earnest, well-dressed man approached the microphone and apologized for the delay. Due to some misunderstanding, less than half of his all boy choir had appeared - and the recording technicians were ready to roll.

''Perhaps,'' the director continued hopefully, ''there are some strong voices in the audience that could help us out.''

The Swedish woman gave me a sidelong glance, which I pretended not to see. The young boys began singing bravely and beautifully, but they numbered altogether fewer than 10 and their sweet voices were swallowed up by the vastness of Trafalgar Square. Once in royal David's city Stood a lowly cattle shed . . .

''You should go up there,'' the Swedish voice urged. ''They need you.''

''I couldn't,'' I whispered back, both flattered and horrified by her suggestion. ''I'm meeting friends soon.''

She stood silently for a moment, listening to the boys struggle against impossible odds. ''With you beside me singing near my ear, I think I could follow the music,'' she said firmly. ''They have books to read from.''

Before I could make another excuse she took my hand and pulled me onto the platform. The relief in the faces of the choirboys was evident. The two of us wouldn't contribute much to the performance, but at least they were no longer fighting alone. Carol books were thrust upon us by eager young hands and beneath a Norwegian Christmas tree a Swede, an American, and the sweet English boys sang a French carol in Latin. Gloria in excelsis Deo! Gloria in excelsis Deo!

I looked down at the crowd of faces glowing in the soft tree lights and thought of the other crowds that had assembled in Trafalgar Square. Over the past 100 years it has seen suffragists and social reformers, protesters against every injustice from rampant poverty to the violence in Northern Ireland. Where we stood singing on this cold December night people had raised their voices for freedom and peace and human dignity. Now our own voices gathered force and swelled above the audience, around the great lions, over the manger, through the cables and into the sitting rooms of listeners throughout the United Kingdom. We sang with the conviction of all those who had preceded us. Peace on earth and mercy mild, God and sinner reconciled!

Our initiative shattered the self-conscious reserve of the crowd. Volunteers scrambled up to join us on the platform until we formed a full choir (''And suddenly there was with the Angel a multitude . . . '') which lifted its collective voice in hope. Hark! the herald angels sing, ''Glory to the newborn King!''

The charity boxes jingled through the audience and came back filled with coins. People laughed and sang and called ''Merry Christmas!'' to one another. Even the great bronze lions of Trafalgar Square smiled majestically, suddenly as much a part of the Christmas story as the oxen and the sheep.