According to the text, why were the Bhagavad Gita and Nath Bhagawat considered so significant in Shirdi?

The Bhagavad Gita, particularly through its commentary Jnaneshwari (Bhavartha Deepika), and the Nath Bhagawat were considered the two main books for daily reading in Shirdi. Chapter 18 explains their significance by describing them as divinely inspired and essential for spiritual attainment. The Nath Bhagawat, containing the dialogue between Krishna and Uddhava, is called the 'loving speech of Nath' and, along with Jnaneshwari, is described as the 'platform for the highest spiritual goal.' Baba ordered their reading for the 'salvation of souls,' believing that those who perform the reading with faith can attain God instantly. This practice formed the essence of the Bhagavat religion that Jog read daily.