How does the act of engaging with holy books, as described in the source, serve as a reminder of the Guru's presence?

The source material from Chapter 27 explains that engaging with holy books is a powerful way to feel the Guru's presence. One of the primary reasons for Sai Baba's collection of books was so that reading them, whether in Shirdi or elsewhere, would remind the devotee of him. This connection is deeply personal; the text states that when reading stories of Rama or Krishna, 'Sai alone is seen before and behind.' It's described as a feeling that Sai himself has manifested in the forms within the books, allowing both listeners and speakers to daily see Sai's idol in front of them, making the texts a living connection to the Guru.