Shirazeh Houshiary, Lisson Gallery, London

In his rather gnomic text From the Book to the Book, the French mystic philosopher poet Edmond Jabès wrote: "Writing... is an act of silence directed against silence, the first positive act of death against death." The art of Shirazeh Houshiary, the Iranian-born painter who was nominated for the Turner Prize in 1994 and who was responsible for the new East window recently created for St Martin-in-the-Fields church in central London, has always had a strong relationship with the word. Writing forms the basis of her elusive and beautiful paintings. Each work has been derived from a word unknown to the viewer, a word that has a relevance for the artist. Like clouds, they appear to hover insubstantially over the solid aquacryl backgrounds.

These canvases seem to ask questions. Is this a painting? If so, of what and what does it mean? But these are the wrong questions. For these are not paintings of objects, nor are they, in the conventional sense, abstract paintings; rather they are emotional states made manifest in paint. Like the whirling dervishes, for whom their twirling dance is one of the physical methods used to reach religious ecstasy, these paintings have a similar (though more secular) function. Their making can be considered a form of meditation and as in meditation concentration on the breath is paramount.

Breath, light, air and the prolonged act of attention are the hallmarks of these ethereal works. The blue and grey pencil marks littered across their surfaces have an otherwordly quality, while those in red and blue read like the colour of skin tinged with light. As in great religious paintings from the quattrocento, such as those by Fra Angelico, light implies a state beyond the quotidian. In Cypher, the blue and grey marks on a white ground suggest the blue of heaven. In Shroud, the screen is impregnated by a breathing presence that's palpable yet invisible. The pink and blue marks look both like linen and flesh.

Also on show here are Houshiary's new series of spiral towers. Made of anodised aluminium, the open bricks are held together by tension. There is a relationship both to the study for Brancusi's Endless Column proposed for a site in Romania, as well as to the columns in Fra Angelico's The Annunciation. They also suggest columns of light or, in their rhythmic movement, whirling dervishes.

These are sculptures and paintings that do not insist. They are dependent on the viewer taking time. As TS Eliot said in "Burnt Norton": "At the still point of the turning world. Neither flesh nor fleshless; / Neither from nor towards; at the still point, there the dance is..."

To 26 July (020-7724 2739)