Aidan Moffat & RM Hubbert @ Old Fruitmarket, Glasgow, 3 Feb

We are in the presence of a master this evening. Was his technique refined over years of trial and error, or acquired instantly after a sordid bargain made with powers beyond our ken? Perhaps it’s best not to know. In any case, you would be hard-pushed to find a musician more committed to the art of selling merchandise than RM Hubbert. Tonight, mid-set, he is dismayed to learn that his constantly-evolving "buy a fucking tea towel" spiel is entirely unnecessary: the tea towels have sold themselves. As have the tote bags. Aidan Moffat turns to his collaborator, similarly deflated, and questions "why are we even here?" before a call from across the hall provides an answer: T-shirts remain in stock. "Buy a fucking T-shirt," Hubbert smiles.

Exchanges between Moffat and Hubbert are as welcome to a sold-out Celtic Connections audience as cuts from Here Lies the Body and Ghost Stories For Christmas; both released last year, and each as strong as any record the two have put their names to in the past. Perhaps these lines from Cockcrow – printed on each item of (admittedly highly desirable) merchandise available this evening – offer a partial explanation for Moffat’s apparent inability to release anything even remotely boring or inessential: 'Don’t let the morning throw away / What the night bestows us / The sun will always have his say / But the nighttime knows us'. Moffat’s concern is, consistently and compellingly, "the things people don’t really talk about".

The intimate truths we gloss over: enchantment, disenchantment, passion and decay. We see aspects of ourselves in Moffat’s characters and scenarios that deserve a little more attention, and are encouraged to look for beauty and joy in unorthodox places. We are also (admit it) simply in need of more songs about sex. Well, songs that aren’t just incredibly enthusiastic endorsements of the idea of having sex. Moffat is interested in the particulars. The lovers entwined: what are they thinking and feeling? What are their bodies like, what were their bodies like? Healthy, important questions to ask. Don't expect to hear 'Our lust is a must! / This sex machine looks knackered / But it’s just a wee bit rust' blasted at a Sex Ed class anytime soon, mind.

Car Song, Moffat and Hubbert’s first collaborative effort, is familiar now but no less emotive, while Fringe and Zoltar Speaks showcase two musicians that are, as always, far from complacency. A storming rendition of Mz. Locum envelops the cavernous Old Fruitmarket with ease, and Jenny Reeve (backing vocals/violin) shines on jubilantly received renditions of Only You and A Ghost Story for Christmas. A haunting new version of Wolves of the Wood is a highlight, and will be released, Hubbert reveals, on Record Store Day. A timely cover of Rosalie Allen’s Hitler Lives ("an anti-fascist country and western song written just after the Second World War") is met with thunderous applause, as are Moffat’s parting words: "Thanks again. Night night. Fuck Brexit."