What initially inspired Cholkar to make a vow to Sai Baba?

The provided text in Chapter 15 indicates that the initial impetus for Cholkar's vow was hearing a kirtan performed by Das Ganu. The scripture states, "Poor Cholkar was from somewhere else; Das Ganu’s kirtan was just a pretext; he felt the desire to make a vow, and Baba was pleased." This suggests that the devotional atmosphere and stories shared during the kirtan moved Cholkar and sparked the faith within him to make his vow regarding his employment examination.