What was the promise Babasaheb Tarkhad made to his son, and why was it so important?

Babasaheb Tarkhad's son was a devout follower of Sai Baba who performed daily worship and offered Naivedya (food offering) to a photograph of Sai. As described in Chapter 9, when the son was asked to accompany his mother to Shirdi, he was worried about who would continue this regular worship. His father was a follower of the Prarthana Samaj, so the son was hesitant to ask him to perform idol worship. The son only agreed to go after his father, Babasaheb Tarkhad, made a solemn promise. He assured his son that he would personally offer Naivedya daily and that no one in the house would consume food before this offering was made to Sai. This assurance was crucial as it maintained the continuity of the son's devotional vow.