IT IS not rare for the Sistine Chapel Choir, known officially as the Cappella Musicale Pontificia Sistina, to venture forth from Rome, where it has served for centuries as the choir of the Pope's personal chapel.

But the chance to hear a choir of such note, close at hand in Westminster Abbey, was uplifting; and, as the Dean, the Very Revd John Hall, reminded us, the insight it brought to alternative ways of approaching Renaissance sacred music in this recital, generously given last month without charge, was particularly inspiring and revealing.

This noble choir dates back to even before the sixth century, when Pope Gregory the Great reorganised and enhanced it on institutional lines. Later improvements were made in the 13th and 15th centuries, when it took its famed name from Pope Sixtus VI. Its key aim is to "express the evangelical mission of the Church", not least by spreading abroad the legacy of some of its most famous former members.

Those celebrated composers include Josquin des Prez, Marenzio, Morales, Palestrina, and, more recently, Don Lorenzo Perosi, who was choirmaster, with intermittent breaks, from 1898 to 1956. The present choir director, Mgr Massimo Palombella, after a highly distinguished career in liturgical music, was appointed by Pope Benedict XVI in 2010. The choir consists of some 20 men and 30 boys.

For a range of reasons, it is relatively unusual to hear anywhere a concert devoted solely to a sequence of works by just one single 16th-century musician. Here, paying honour to the Renaissance composer in which they specialise and excel, Mgr Palombella decided to focus on the most celebrated of all: Giovanni Pierluigi da Palestrina, who was appointed music director of the then Cappella Giulia (the choir of St Peter's Basilica) in 1551.

A strikingly prolific composer, Palestrina continued to work in close collaboration with the Vatican, and also in sundry churches in Rome, including the papal basilica of St John Lateran, till his death in 1594.

As the Dean suggested, we were all the richer for this rare musical gathering. If any ensemble was deeply versed in managing the tenors' pianissimo opening to the plainsong "Christus factus est", or in sustaining monody so tenderly and beautifully, this was it. One of the tricky devices at which the Sistine choir perhaps uniquely excels is those tiny sforzandi that Mgr Palombella teases out from men and boys, which lend special vibrancy to, for instance, their nuanced opening of the Gloria of Palestrina's probably best-known mass, Missa Papae Marcelli.

Like the Mass, Palestrina's ensuing Stabat Mater reflects his earnest response to the demands of the papal authorities, in tune with the Council of Trent's findings, for restraint in word setting and moderation in counterpoint. Here the choir was divided, with a consequent clarity. In the stanza "Adoramus Te, Christe", some confident altos brought added colouring and expressiveness to the words, lending fervency to the whole ensemble.

Mgr Palombella, used to responding to the specially intimate acoustic of the papal chapel, conducted almost the whole concert at mezzo forte, or a lesser volume. The men, therefore, showed throughout a considerable, rare restraint. Owing to this slightly sclerotic stylisation, these patently musical boys also sang with only part-opened mouths: consonants were sometimes less than ideally defined, and the vowels acquired only moderate definition: a very different, less tangibly passionate impact from what one would hear from their opposite forces used to the ambient spaces of the Abbey, its choir and north and south transepts.

Hence the burst of wind in Palestrina's vigorous "Dum complerentur dies Pentecostes" scarcely blew or blustered at all; while, instead of dancing, most alleluias were sung so delicately as to sound almost apologetic. Yet all the cadences were handled in an intriguingly mannerised, drawn-out style by Mgr Palombella - a very individualistic and striking effect, and arguably different from the treatment offered by almost all leading English choirs.

Where the ultra-restrained Sistine Chapel choir really excelled, and showed their men's and boys' true gifts and musical verve, was when - at last - they "let go". That was in the final two pieces: a vital "Veni, dilecte mi", finely poised despite the odd tame line (sibilants aside, how does one lucidly emphasise the fricative, labial, and liquid consonants of "si flores fructus parturiunt, si floruerunt mala punica"?); and the wonderful "Tu es Petrus", which, of course, we associate today with joyous welcomes to Pope Benedict and now Pope Francis.

This last, not unlike a papal national anthem, was sung with breathtaking beauty, power, and warmth, and a depth of feeling which one would find hard to match. Men and boys - so perfectly in tune and harmony throughout this concert - produced a wonderful vigour and stimulus that goes with profound familiarity, and was outstanding and uplifting. This splendid Vatican choir does have fire; I just wished that they had been allowed to get up steam more often.