Arvo Pärt bookended the first half of this varied ecclesiastical programme. The Lammermuir Festival Players under the direction of a very dapper Christopher Bell opened with Arvo Pärt's Summa. Within a few bars it seemed clear that this performance breathed like no other I'd heard. The wonderful acoustic of St Mary's Parish Church certainly enhanced this interpretation. One could hear the 1977 choral origins (a Credo setting) informing Pärt's 1991 string orchestra version. Bell's impressive choral pedigree was no doubt a factor here and tenderly played lines for violas and double basses seemed effortlessly to emerge. At around five minutes, this short Creed setting highlights Pärt's minimal and largely syllabic approach to text and, more noticeably here, to resultant melody.

Pärt's 1976 Fratres mirrors Summa in that it was originally composed for string orchestra before rivalling Dr Who for regenerations. The pacing in this fine performance highlighted Pärt's beautifully simple architecture. Phrases of increasing length snake around a central note before being inverted. Each section begins on a new note and the angular intervals used guarantee striking contrast from apparently similar material. String textures in this quietly gripping performance varied from the ethereal to the corporeal while never fully exiting the quiet ambit of monastic office suggested in the fraternal title.

The Pärt works were separated by Philip Sawyer's lively rendition of Veni Creator from the sole surviving work, Livre d'Orgue of Nicolas de Grigny (1672-1703). Throughout five short movements, Sawyer's articulation seemed to echo Bell's take on Summa, there being more breath and light than one might imagine possible, especially in the closing "Dialogue sur les grands jeux". Lively counterpoint informed most moments, even the titularly declarative "Récit de cromorne" (Krummhorn Recitative). Fine execution of mordants, trills and nifty pedal work in "Fugue à 5" added to the music's adventurous harmony.

Although Duruflé s 84-year lifespan dwarfed that of his compatriot Grigny, fierce self-criticism prevented his surviving catalogue from reflecting this. The undeniable quality of his 1947 Requiem Op.9 along with the existence of three versions suggest that it passed muster for Duruflé. Choral input was here supplied by the 41-strong National Youth Choir of Scotland Chamber Choir, drawn from the 100+ members who top the pyramid of Scotland's choral training programme, established in 1996 by artistic director and conductor Christopher Bell.

Contrast with Pärt's syllabic inclination was obvious from the opening bars of the Introit, given over to fine sounding melismatic tenors and basses, underpinned by gently undulating violas and, later, fluty organ and trumpets. Knowing that the work was written for Duruflé's father, it struck me in the explosively delivered "et lux perpetua" that it would be impossible to contain one's emotion were this a personal farewell as opposed to a "requiem for enjoyment". The music continued without pause into the six-word Kyrie whose soaring breadth, wonderfully shaped here, denied the brevity of its text. As in the Introit, dynamic range and control were impressive; the expressive commitment of these young singers was stunning and life-affirming.

Following some changes in organ registration, the Domine Jesu Christe offered as fine an illustration of Duruflé's thorough modal schooling as one could seek. The angular organ introduction hinted at the Byzantine origin of Gregorian church modes. There was infectious urgency in the delivery of Libera eas de ore leonis which later settled in the presence of a tenderly delivered melody for the orchestra's three cellos.

Then from the ranks of choir emerged the baritone soloist, Arthur Bruce. His rich voice crescendoed movingly through "animabus", settling before tremolo strings ushered in the work's key reflection, "morte". The atmosphere in the Sanctus was, by contrast, optimistic, from the nifty organ opening, through the choir's initially gentle harmonies, energised by pizzicato strings, to the joyous "excelsis" helped along by brilliant trumpet playing. The movement's closing rallentando was beautifully handled.

Mezzo-soprano Katie Grosset's Pie Jesu was lovely. Beginning in a very low tessitura, her soulful petitions rose to reveal excellent control of an impressive range - all of this tenderly accompanied by Philip Sawyer on organ and Martin Storey's solo cello.

One way to accompany a beautiful melody is with another, which Duruflé achieved in the string part of the Agnus Dei - an embarrassment of melodic riches lovingly delivered here. The gentleness of the Lux aeterna was very affecting and the consequent contrast in the following Libera me striking. Baritone soloist Arthur Bruce dramatically delivered the work's only mention of the Dies irae. Like his compatriot Fauré, Duruflé was offering comfort, not terror. Nevertheless, the expressive power in Bruce's voice was dramatic.

The closing In Paradisum was transcendent, its unfinished-sounding final chord suggesting hope. This was a really fine performance, warmly received.