What was the vow that Cholkar made, and what challenges did he face in fulfilling it?

Cholkar's vow was born out of necessity. As a poor man, his livelihood depended on passing a crucial examination to make his job permanent. Chapter 15 explains that he made a firm resolve to Sai Baba: if he passed, he would go to Baba's feet in Shirdi and distribute sugar candy in His name. Although his prayer was answered and he passed the exam, he faced the significant challenge of poverty. The text poetically describes this worldly struggle as a 'threshold-ghat' (referring to home expenses) that is very difficult to cross. He simply did not have the money for the journey and had to postpone his pilgrimage from 'today to tomorrow' until he could finally afford to go.