Shepherds throw the best parties- Der Herr is mein getreuer Hirt- Cantata for the second Sunday after Easter

Bach is fed up. He's been denied the resources to do his job properly and is not happy about it. This week's cantata comes from April 1731, well after Bach's astounding rush of creativity of 1724-25 when he was inspired to produce a new cantata every week. Then, he seemed content in his new job as Kantor, the lynchpin of the musical life of Leipzig. Now, it's a different story. The previous August, he wrote a memorandum to his employers complaining that a large chunk of the so-called choristers at St Thomas' School did not “understand music at all and can barely sing a chorale with difficulty”- “so keine music verstehen, sondern nur nothdörfftig einen Choral singen können”. His astounding flow of new weekly cantatas has slowed down to a dribble. Is Bach just bored of getting his boneheaded pupils to sing new masterpieces?

Part of it is that by now, Bach has done a large chunk of the task he set himself- to provide a “well-ordered church music”. He's composed at least two more or less complete cycles of music for the whole church year. There are only a few gaps to be patched. Some of these gaps are due to the weirdness of the liturgical calendar. For example, there are rarely twenty-seven Sundays between Trinity Sunday and Advent, so Bach only got round to writing a cantata for that particular obscure Twenty-Seventh Sunday after Trinity in November 1731. Ironically, that's a stunning masterpiece, and probably the most famous of all cantatas- Wachet Auf, ruft uns die Stimme. So we can't say that Bach was just sick of church music by the early 1730s. But he was certainly spending more time writing secular music for the caffeine addicts at Zimmerman's coffee house than new cantatas for the congregation at St Thomas's.

So this cantata is brief- shorter even than the single alto movement from last week's instalment. But never mind the length, feel the quality! The text is a 1530 metrical translation of Psalm 23, “The Lord is my Shepherd: I shall not want”. It's the one that everyone has heard at their grandparents' funeral (including mine, for that matter). Nearly every other composer, from Schubert to Howard Goodall (he of the Vicar of Dibley theme tune) sets it gently and pastorally., even Bach himself takes that option in his earlier settings, you can usually smell the fields. Bach goes for a completely different option here- pompous, lordly. Here, the shepherd is just a metaphor; what we hear in the opening chorus is the entry of a Lord equal to any of Bach's patrons.

For me, the first movement exemplifies the baroque courtly aesthetic. It's not easy listening: the orchestral textures are quite complex. The sheer weight of independent musical parts makes it sound dense, like a rich-fruit cake with all sorts of nuts and unexpected sweetmeats beneath the surface. In fact, it took me a couple of goes to get into it. I was overwhelmed by all the colours, especially the horn flourishes over the top.

It didn't help that Masaaki Suzuki's recording with the Bach Collegium Japan really brings out the edgy tuning of the woodwinds here. For once, I thought that Ton Koopman with the Amsterdam Baroque Orchestra was a better guide. His scholarly calmness works for me here, when occasionally it can just sound dull in less colourful music. Nevertheless, we sometimes we need reminding that music from the eighteenth century can still sound plain weird at times! It certainly sounded odd to Bach's contemporaries; this is the sort of music that the generation after Bach rebelled against, and even some of Bach's sons bought into the new Classical simplicity and coolness.

The alto aria that follows has a lovely swing to it. I don't know why writing in time signatures like 6/8 and 12/8 is considered “pastoral”; most sheep and sheepdogs have four legs, not three, and shepherds don't waltz much. But both Handel and Bach slip into lilting compound rhythms when they want to talk about shepherds, whether in Arcadia or Palestine. And here we hear a flowing, bubbling brook of an oboe part as the soloist sings “Zum reinen Wasser er mich weist,  Das mich erquicken tue.” - “he leads me to pure waters that enliven me”.

The bass takes the next verse: he starts with an arioso on the words “Though I walk through the dark valley, I fear no misfortune”; it's not quite a full extended aria, but has some of the declamatory aspects of recitative instead. There's some lovely murky double-bass work on the words “finstern Tal”- dark valley- as the music ventures into all sorts of harmonically unexpected places, but then returns to bright simplicity for “Dein Stab und Stecken trösten mich”- your rod and staff comfort me.

And just as in the psalm, the move from the dark valley to the feat is almost immediate.There's a real bounce to the soprano/tenor duet that follows; each vocal soloist rushes up toward the top of their register in the first few bars; the whole mood fits in with the words “Machst mein Herze unverzagt und frisch- you make my heart undismayed and fresh.”. The whole section has something of the air of a country wedding, with Freuden- joy- ringing out again and again through the dance-rhythms. We end with a chorale made additionally burnished and brassy with the oboes and horns joining together to make a slightly archaic sound-world- but one that's clearly full of joy. The chorus sings“ich werde bleiben allezeit im Haus des Herren eben”- “I shall remain in forever in the house of the Lord”. It's a vigorous, embodied rejoicing in the physical presence of God. Bach's Lord may be a shepherd; but his shepherd is also a Lord, and he throws great parties.