Can you explain the philosophical basis of the yoga associated with Sai Baba, as mentioned in the texts?

According to Chapter 4, the yoga associated with Sai Baba is deeply philosophical, focusing on the realization of non-duality. He is called the "Lord of Yoga" who appeared on the Godavari for the world's upliftment. The core principle is recognizing that "everything—moving and unmoving—is Brahman by nature." This leads to a state of oneness where one realizes "I am everything." When this "I-ness" is attained, enmity and fear dissolve because nothing is perceived as separate from the Self. His yoga was the attainment of this supreme state, where his mind was constantly colored with the form of the Self.