Why was staying in the dilapidated Chavadi considered the proper 'medicine' for Amir Shakkar's rheumatism?

The true medicine for Amir's rheumatism was not a physical treatment but a spiritual one centered on faith and proximity to the Guru. Chapter 22 explains that although the external conditions of the Chavadi were contrary to healing—with dampness, wind, and cold—the internal condition of faith was paramount. Baba's firm words were the actual medicine, and the constant company of Sai was considered the 'Great Prasad.' By accepting Baba's word and staying in the uncomfortable place, Amir's internal faith was strengthened, which was the core of the healing process.