What was the specific vow Cholkar made to Sai Baba and why was he unable to fulfill it immediately?

Cholkar's livelihood depended on passing an examination to make his job permanent, and he was facing financial hardship. As described in Chapter 15, he made a firm resolve to Sai Baba that if he passed the exam through Baba's grace, he would visit Shirdi and distribute sugar candy (khadisakhar). After his wish was granted, he experienced a delay in fulfilling the vow. The text explains that for a worldly man, crossing the "threshold-ghat" of home expenses is very difficult, implying he lacked the financial means for the journey to Shirdi and had to postpone it.