According to the provided text, what is the significance of the Jnaneshwari and the Nath Bhagawat?

The text holds these two books in the highest regard, presenting them as divinely inspired and essential for spiritual progress. Chapter 18 describes the Nath Bhagawat as containing a sweetness that is impossible to describe, calling it the 'loving speech of Nath' and a platform for the highest spiritual goal. The Jnaneshwari, a commentary on the Gita, is also presented as a primary and essential text. The fact that the 'merciful capable Sainath' made it a daily practice for these books to be read in Shirdi underscores their immense importance in his teachings for the welfare and salvation of devotees.