Tonight Bach and Handel unite as two writers of timeless work, being rendered by a choir whose home turf is a 13th century building of awesome beauty, and an Oxford ensemble dedicated to the accurate performance of baroque and classical works. This evening is a bit of a treat and a retreat, a gift of 'stepping out of time' into somewhere filled with music of the sacred and numinous, as the audience is contained by a centuries-spanning mosaic of tiling and elaborate stained glass. The programme sees baroque masters looking to other eras and pushing the limits of what was musically possible in their own.

Firstly, Bach's motet Singet dem Herrn sees the mature composer both looking back and bringing things up to date, with musical material from Martin Luther cropping up in this sacred work. In the singing, it's brisk and jubilant – a concerto-form hymn of praise, with slow-paced pleas for divine accompaniment in the central movement. Choir Director and Conductor Benjamin Nicholas brings out this happiness, allowing for no excesses in pace – though he does have forces to keep in check, as the basses are being carried along by pacey melisma passages. It's certainly a challenge to perform – and this ensemble of undergrads and postgrads carried this piece well. A little more clear enunciation around the 'Singet' exhortations could've brought out the impishness of these calls to worship, but the acoustic likely made such an effect difficult.

Christ lag in Todesbanden, an earlier cantata, summons to the front of the chapel Instruments of Time and Truth, superheroic in their period finery. In recordings I've heard this magnificent piece made somewhat ponderous, but the approach tonight is admirably restrained, certainly partly contributed by the authentic baroque instruments and concern for conventions of the very early 1700s. Here their m.o. allows echoes of earlier composers to reverberate (harmonic reminiscences of Purcell's 'Here the Deities Approve'), and perhaps gives a window into how J. S. Bach would have heard his inventive set of Luther variations. The whole is wondrous, but the second section is particularly revelatory – soprano (Carys Lane) and alto (Jeremy Kenyon) perform the opening phrase in stereo, from either side of the chancel, and present the text about humankind's fallen state. It's the only text in the piece without any redemption. Kenyon's performance is sensitive and confident; Lane's, wonderfully vulnerable and agile. When they reach the perfunctory closing word, it's a cold and it's a broken hallelujah.

All performers combine to great effect in the climax of our programme – Handel's florid Dominus Dixit showcases the luminous texture of string suspensions, stentorian homophony (well, it is "The Lord said…" after all) from our choral forces and coloratura passages, like twisting vines, for these talented soloists to negotiate. That's all in the opening movement. Even when the style of writing is not to my taste, the performance inspires – soprano Nicki Kennedy's range, control and tone shine in Tecum Principum, the melody being traced in smooth descending triplets – when they harmonise with the strings, the effect is sensational. Instruments of Time and Truth have been producing great, multi-dimensional sound-fields all evening. Think period instruments, and the texture that comes to mind may be a bit thin – here, anything but. The richness of the scoring is evident, from violins down to organ-and-bass continuo. Turning here to the composer from whose work they drew their name, they bring out the depths of a piece that revels in the elaborate style of its time.