I don’t often get so grabbed by a half-heard piece of music that I have to drop everything to listen properly, but it happened the other day. I was in the kitchen defrosting the fridge and across the hall Radio 3 was playing in the living room. The evening concert was Mozart’s arrangement of the Messiah. This was I think the arrangement used in my first ever performance, and I’ve sung it at least once since. This performance was ‘authentic’ in that it followed Mozart’s directions and did not (as some do) revert to Handel’s obbligato in The Trumpet Shall Sound. (Clearly Mozart didn’t have an adequate trumpeter, and the addition of discreet accompaniment to Since by man came death suggests his chorus couldn’t sing in tune either.) And there is the peculiar moment when you get the recitative that introduces Let all the Angels of God, but not the chorus itself. Overall the effect is rather as if you are observing Handel at work, when from time to time there is a skirl on the flutes and a guy in a periwig bobs up and waves at you. There is an added solemnity, though, which I attribute to the addition of trombones.
What stopped me in my tracks however was He was despised. I’ve always found this a little tedious, sitting in the chorus chomping at the bit waiting for Surely he hath borne our griefs which is my favourite movement to sing. But in Mozart’s orchestration it becomes staggeringly beautiful. I think it’s something about the way he uses the clarinets. It really is like a stray bit of the Requiem which got away. In fact, I can hear at one point a prefiguration of the repeated chords which introduce the Osannas in that work. But wait a moment – that bit is usually said not to be by Mozart! Are the chords just an 18th-century topos which Süssmayr used, or had he studied Mozart’s Handel for inspiration? Or did Mozart somehow communicate to him that that was what he wanted at that point in the Requiem?