Can you explain the concept of the 'speech-sacrifice' (Vag-yagna) as described by the author in Chapter 45?

In Chapter 45, the author refers to the creation of the Shri Sai Satcharitra as a "speech-sacrifice" or "Vag-yagna." Portraying himself as a person of little knowledge, he humbly offers this book to the readers. He requests the "all-knowing listeners" to accept this literary offering with a grateful heart. The author expresses his hope that this auspicious sacrifice, which puts an "ignorant one like me forward," will be successfully completed by the Guru's grace. This concept, as detailed in Chapter 45, highlights the author's deep humility and the devotional nature of his work in chronicling Sai Baba's life and stories.