Based on the provided texts, what is the 'natural tendency' of Sai Baba's Udi and what is required from a person for it to work?

The power of Sai Baba's Udi is described in Chapter 35 as having a "natural tendency" to remove trouble. However, its effectiveness is linked to the recipient's state of mind. A devotee explains this principle by stating, "If you too keep faith, the Udi will manifest its influence." This highlights that faith is a key component. The story of the man from Bandra suffering from bad dreams reinforces this. He was told to apply the Udi and, most importantly, "remember Shri Sai in your mind" and "keep devotion in your heart." The text suggests that when this faith and devotion are present, the Udi's influence will immediately resolve the problem.