An article at the BBC caught my eye recently.
The spring of 1825 was not good to Beethoven. Possibly due to his deafness, or else his angry mood swings, he felt increasingly isolated from his friends and family, complaining to his nephew about “you, and my contemptible brother, and the detestable family that I am afflicted with”. Beethoven’s own erratic behaviour may have pushed people away, too. As a servant remembered in an incident the following year, their master would “wander in the fields, calling, waving his arms about, moving slowly, then fast, then abruptly, stopping to scribble in his notebook.” Between that and his shabby appearance, 1825 even saw Beethoven detained by police – after they mistook him for a vagrant.
Worse was to come. In April, Beethoven developed a serious intestinal illness. His doctor ordered him away from Vienna for rest at the nearby spa of Baden, and banned him from drinking wine or eating his favourite liver dumplings. As Robert Kapilow, a composer and musical commentator explains, Beethoven adored the countryside, but this trip away would be far less enjoyable. His exact condition is unclear, but from his letters he clearly feared for his life – especially when combined with his fragile mental state. “Forgive me in consideration of my very delicate health,” he wrote to the writer and critic Ludwig Rellstab at the start of May 1825. “As perhaps I may not see you again, I wish you every possible prosperity. Think of me when writing your poems.”
In the end, Beethoven did get somewhat better – and it was while recovering at Baden that he wrote the Heiliger Dankgesang [the third movement of the String Quartet 15 In A Minor, Op. 132]. Even if a dumpling-free diet really did help his recovery, the composer himself looked to a higher power. As he notes, the movement is a Holy Song of Thanksgiving of a Convalescent to the Deity, in the Lydian Mode. “It is clearly a statement of faith,” explains Edward Dusinberre, first violinist in the Takács Quartet and an expert on the Heiliger Dankgesang. “You observe that in people who have had extremely hard lives – they have found that attitude of gratitude.”
There's more at the link. Interesting reading.