What is 'Prayopavesha', and how does the story of the Deshmukhin in Shirdi demonstrate this concept?

The term 'Prayopavesha' refers to a deliberate fast unto death, undertaken to fulfill a solemn vow. The story of Radhabai Deshmukh in Chapter 18 provides a powerful demonstration of this concept. Driven by an intense desire to receive a spiritual instruction, or mantra, directly from Sai Baba, she undertook a severe penance. She renounced all food and water, engaging in what the text calls a 'dharna' (fasting protest). Her resolve was so absolute that the narrative explicitly states her intention was to 'fast unto death (Prayopavesha)' until Baba granted her request, showcasing the extreme lengths her faith and determination took her.