There was much cause for celebration at St George's, Hanover square on Tuesday night. The early evening concert marked exactly 25 years of the quirkily named ensemble Revolutionary Drawing Room, a birthday they shared with the composer whose work they played, Franz Joseph Haydn. However, far from the festive fare that one would usually expect to be on offer on such an occasion, the programme presented was of a sombre tone: the Seven Last Words of Our Saviour on the Cross. Not exactly what you'd call party music, but given that the special day fell this year within Holy Week, it was a decision that prioritised the liturgical calendar and its annual celebration of Christ’s Passion over more mundane birthday celebrations.

Haydn's Seven Words is a strange piece in many ways. Existing in three forms – an orchestral version, a string quartet version (which we heard at this concert), and a oratorio version – it belongs to a musical tradition stretching from Heinrich Schütz to Sofia Gubaidulina, in which the composer responds to the last utterances of Christ, taken from across the Four Gospels. Haydn's orchestral version was written for the cathedral at Cádiz, in which it played a key role in the liturgy, providing time and musical material for reflection after the bishop had preached on each of the Cross words.

 However, extracted from its liturgical context, the link between Haydn's music and its subject becomes more problematic: do away with the title, and you're left with nothing more than nine conventional musical movements, which, apart from avoiding the sparks of jovial brilliance of much of Haydn's instrumental writing, show very little evidence of the religious subject matter that is so central to them. In other words, the music, with its sonata form conventions (first subject, second subject, development etc.), seems disconnected from its meaning. It's a problem of matching form to content: one which is exacerbated in the string quartet version, with the genre's emphasis on abstract musical form, and equally in its lack of contrasting instrumental sonorities. Given the wealth of extraordinary pieces which harness all music’s power to bewail, lament and present the pain of the Passion, the regular major-key movements in Haydn’s score – some sweet, almost lullaby-esque – come as a bit of a shock, leaving the (modern) listener somewhat nonplussed as to the relation with the horrific events of the Crucifixion.

 In an attempt to reinforce the link with the Passion, Revolutionary Drawing Room's performance was interspersed with mini-sermons on each of the Seven Words. They were given by a priest whose name – not in the programme – I didn't catch when it was announced; his words were pretty basic reflections on the significance of Christ's. Although the connection with the original performance of the work was obvious, these interjections lacked the sort of insight which would have made me see them as something other than a perfunctory nod to tradition. They added very little, and even served to broaden the gap between subject and substance, as I struggled to equate the words pronounced to the music performed.

 The piece may be about Christ's Crucifixion, but there was very little passion in the performance. Granted, the music is understated, reflective (though not especially meditative), and so artistic exuberance would be entirely out of place, but the reserve with which the ensemble played betrayed a lack of engagement with the performance, not simply a respect for its devotional nature. There was rarely any intensity to the playing, but when it did come, it did wonders, transforming the music from a state of detachment to a much more moving level of emotional expression.

 Perhaps the period instruments were to blame for my dissatisfaction with the quartet's sonority, which rarely seemed to settle into that satisfying string quartet soundworld exemplified in so much of Haydn’s quartet writing. But there were times when this was achieved, such as in Sonata IV ('Deus meus'), with its yearning upwards sequences, and in the final Earthquake section, which was really excellent: full of the energy and ensemble precision that had been conspicuously absent in much of the preceding music. Perhaps it was the instruments, too, that meant intonation was a persistent problem for all four players, at times reaching quite excruciating extremes. Again, though, when passages that were problematic on this front returned later in the music, they usually did so with much improved tuning. There were times when really beautiful textures and timbres were achieved, most notably the muted penultimate movement, which provided a tender cradle for Christ’s Final Word.

These moments of quality showed that Revolutionary Drawing Room certainly had the capacity to make more of this performance. Their relative scarcity made for a frustrating concert, overall – one which I’m sure is not representative of a quarter of a century’s work.