How did Sai Baba use Udi to grant permission for devotees to leave Shirdi, as explained in Chapter 33?

As detailed in Chapter 33 of the Shri Sai Satcharita, Sai Baba had a specific method for granting devotees permission to leave Shirdi. When devotees would approach him to ask for leave to return to their villages, Baba's true consent was conveyed through the act of giving them Udi. The text states that when Baba said, 'Take the Udi,' this was understood to be the actual permission to depart. This practice was well-known among all the devotees, and receiving the Udi for their journey would fill their minds with enthusiasm and assurance for their return home, turning a simple departure into a blessed event.