What was the 'medicine' Sai Baba prescribed for Amir Shakkar's rheumatism, and what were the conditions he had to endure?

According to Chapter 22, Sai Baba's remedy for Amir Shakkar's rheumatism was not a physical medicine but a test of faith and endurance. Baba's firm instruction was for Amir to stay steadily in the Chavadi. This was a challenging prescription, as the Chavadi was an old, dilapidated building described as being full of lizards, scorpions, garbage, and dampness. The text notes it was a place of wind and rain, with uneven ground and seventeen knee-deep holes, making the external conditions completely contrary for someone suffering from rheumatism. Despite this, Amir was told to accept Baba's word as the ultimate medicine and remain there, which he did for nine months.