How does the Shri Dnyaneshwari, as quoted in the preface, describe the process of acquiring knowledge from a Guru?

The Preface (Chapter 0) references the Shri Dnyaneshwari to explain the path to spiritual knowledge. Lord Dnyaneshwar Maharaj states that to bring knowledge into your mind, you must "serve the saints with your entire being." Service is presented as the very "doorway" to the treasure of knowledge. This process involves a complete surrender of body, mind, and soul at the Guru's feet, performing all service without ego. It is after such selfless devotion that the Guru will bestow the requested knowledge, which in turn "will enlighten the heart" and ensure that "doubts will not arise."