How does Dnyaneshwar Maharaj advise a seeker to approach a Sadguru in order to receive true knowledge?

The preface references the teachings of Lord Samarth Sadguru Dnyaneshwar Maharaj to outline the path to knowledge. As mentioned in Chapter 0, he advises that if you desire to attain beautiful knowledge, you must serve the saints with your entire being. This service should be performed with body, mind, and soul, surrendering at their feet without any ego. By making service the doorway to the treasure of knowledge, a seeker can receive enlightenment from the Guru that dispels all doubts from the heart.