The chandeliers slowly dimmed, leaving candles in flickering circles around the rows of cream and gold columns and in a line high above the altar. The conductor, Graham Caldbeck, raises his baton and the cornets, sackbuts, recorders, violins and the long-necked theorbo launch into the joyful opening bars of Monteverdi's 1610 Vespers For The Virgin Mary. Then the Nonsuch Singers rise as one and break into 'Deus in adiutorium meum intende' (O God make haste to save me). The ethereal voices of the choir and soloists reverberate in the hard acoustic shell of the church and for the next hour the capacity audience in this beautiful baroque place of worship in the heart of London are transported, via Monteverdi's sublime score, to musical heaven.
Monteverdi's Vespers are grand and operatic, a cross between the discipline of the old Renaissance style and the ornate splendour of the baroque in which dances and concerti intermingle with more traditional sections. For the believer the Vespers are sublime worship, for the non-believer the aesthetic high they bring can come as close to a religious experience as an atheist can get.
In the interval before the Magnificat, the final section of Vespers, we left our pews and wandered out on to the raised stone platform outside with its panoramic view of Trafalgar Square. The night sky was crossed by a powerful funnel of light that illuminated the statue of the one-eyed, one-armed Lord Horatio Nelson standing precariously atop a granite column 60 metres above ground.
When the concert ended it seemed almost sacrilegious to applaud; after all, we had just listened to an extended musical prayer to the Virgin Mary in a church that has been on the same site in various architectural forms for the past 700 years. But applaud the audience did and the brown-haired tenor with a Mohican ridge of bottle-blond hair running down the centre of his scalp bowed before us along with the other soloists and choir.
The church in which this heavenly concert took place was St Martin-in-the-Fields, the most famous of the many London churches that double up as venues for classical music as well as worship. Mozart gave a concert here while living in London and Handel used to play the original organ. The most-recorded orchestra in the world, the Academy of St Martin-in-the-Fields, founded by the illustrious Sir Neville Mariner, has its spiritual home in the church and the BBC World Service regularly broadcasts concerts from there.
Each season St Martin-in-the-Fields hosts a varied programme of concerts and recitals. The box office is in the basement vault, which is also home to a popular restaurant.