NEW YORK — Composer Sir John Tavener was feted by another knighted Briton, Sir Paul McCartney, and others at a concert Thursday at the Church of St. Ignatius Loyola.

Tavener, one of Britain's most popular living composers, guest-conducted and played organ on several works.

The eclectic program also featured performances by one of Britain's most acclaimed early music vocal groups, the Tallis Scholars, soprano Patricia Rozario, the Flux Quartet and the Manhattan Brass & Percussion Ensemble.

The biggest draw of the sold-out event, however, appeared to be McCartney, who joined the Tallis Scholars as the narrator in Tavener's In the Month of Athyr, a short a capella work based on a poem by C.P. Cavafy.

Elegies were the impetus for several pieces on the program as well. Tavener's austere, meditative music — luminously performed by the Tallis Scholars — commemorated deceased friends and relatives, from the opening Parting Gift for Tam Farrow (receiving its world premiere), through the Funeral Canticle, Song for Athene, and The Hidden Treasure.

This latter work, a string quartet infused with Eastern-sounding minimalist gestures, received its U.S. premiere by the Flux Quartet. Yet inserted midway through the second half of the program, the long and rather demanding work had the unintended effect of driving many weary audience members to the exits.

Those who remained witnessed the finale, A New Beginning, which was billed as a world premiere of a new ensemble arrangement. Originally commissioned for a performance at the 1999 New Year's Eve party at London's Millennium Dome, it evidently was overshadowed by the revelry at the time. Here the combined forces of the Tallis Scholars, Flux Quartet, soprano Rozario, and brass and percussion succeeded in providing a glittering end to an otherwise solemn event.