What exactly did Babasaheb Tarkhad promise his son so that he would agree to make the trip to Shirdi?

To convince his son to travel to Shirdi, Babasaheb Tarkhad made a very specific and solemn promise regarding the daily food offering. The son declared that his journey would not happen unless his father agreed that no one at home would eat without first offering Naivedya to Sai. According to Chapter 9, Babasaheb Tarkhad accepted this condition wholeheartedly. He assured his son, saying, "Go, I will offer Naivedya daily; be certain." He further cemented his commitment by stating, "Without first dedicating to Sai, no one will consume food. Take this word of mine as proof; do not doubt, go in peace." It was only upon receiving this firm assurance that the son felt comfortable leaving.