Based on the provided text, can you explain Sai Baba's philosophy on His true nature and how it relates to desire?

In Chapter 3, Sai Baba explains that His physical body is perishable, but His true nature is the imperishable Brahman, which is the real object of worship. He identifies Himself with the eightfold nature (Ashtadha-prakriti), stating that He is filled in all of creation, both moving and unmoving. Baba teaches that He is everywhere, in all ten directions, and there is no object different from the Self. When one understands this truth and dissolves the sense of 'I' and 'mine', desires naturally cease to exist, dissolving like hail in the sun, because the Soul, which is Baba's very form, has no impulse for desire.