The weekend began in a mood of resistance (Boris Godunov) and ended in a hundred shades of defiance (Shostakovich's Symphony No 4). In between, 2,000 years of Christianity were wrung through the hands of one Russian soul – Sofia Gubaidulina. The Kirov were at the Proms and didn't we know it.
To hear this company – this orchestra, this chorus, these soloists – in the repertoire that they live and breathe daily is something unique, something easy to recognise but more difficult to define. It has to do with a relationship with their conductor, Valery Gergiev, which has now moved beyond mutual understanding to a kind of musical symbiosis. They breathe as one. They phrase as one – complex, subtly nuanced phrases. There's a little bit of Russian history in every inflection. Then there's the colour, the nature of the sound. All those present at Saturday's concert performance of Musorgsky's original seven-scene version of Boris Godunov will have taken the memory of it home with them. The dark, grainy voices of the chorus, a sound of such quiet intensity that a single line of orthodox chant barely murmured from the back of the platform would fill the Albert Hall.
Hear those voices and you are on the steps of the Cathedral of the Assumption within the Kremlin for Boris's coronation or deep inside the Chudov Monastery. There's actually no such thing as a Kirov "concert performance" of anything, leave alone Boris. You are there, right there in the Mariinsky Theatre. A potent theatricality informs every bar. The stakes are raised with every bar. Because every bar is essential, every bar counts for so much in the miraculous concision of Mussorgsky's original. It's extraordinary to watch every last bit-part player in this proud company hanging on to every last word of their fellow performers; to see the magnificent Vladimir Ognovenko (Boris) rising from his chair instantly to assume the highest authority. What an artist this man is. When he died it really was possible to believe that he'd at last found some vestige of humility. And as Gergiev's strings bestowed their final benediction upon him there was a moment or so when I wasn't at all sure that I'd ever heard a more beautiful sound in this hall.
"In the beginning was the Word, and the Word was with God." That's a pretty good opening line. For the faithful few that gathered the following afternoon for Sofia Gubaidulina's Passion and Resurrection of Jesus Christ according to St John, the sounds that accompanied it were strongly redolent of the Apocalypse visited upon Boris's Coronation. The clamour of many bells; the gathering of many voices; and the first of several seismic organ solos exploding across the sound spectrum. If the Book of Revelation (the composer's other source) had a sound, this would be it. Something to put the fear of God into us all. Passion, indeed.
But Gubaidulina's storytelling is centred on the slow, expressionless, monotonal basso profundo chanting of the Russian Orthodox liturgy and St John's words finds only intermittent drama and humanity in Gubaidulina's "other self" – music reflecting her deeply rooted kinship with music from Glinka to Shostakovich. When those musics surface in fleeting lyric wind or string or vocal solos, or when she takes a more literal line on such episodes as St John's vision of the "Book of Seven Seals" or "The Road to Golgotha" where half the chorus cry out in recognition of Christ's sanctity, the other half angrily deny it, the effect is profoundly theatrical. But orthodoxy will out and the great length of its unfolding – testing endurance to the limit – once more raised doubts as to whether such an experience, for all its strange, hypnotic power, really belonged in a concert hall.
No doubts whatsoever about Gergiev's stupendous account of Shostakovich's anarchic Fourth Symphony. That a work of such prodigious talent could have languished unperformed for a quarter of a century only to bounce back with redoubled force tells you all you need to know about the indomitable Russian character. There was a lot of it about this weekend.
Prom 48 (Shostakovich) can be heard at www.bbc.co.uk/proms until 1 Sept