We are teaching our disciples to address amongst themselves “prabhu.” This is not new thing. This is very old. Now Narada is addressing Vyasadeva, “prabhu,” his disciple. His disciple, he’s addressing prabhu. So we should give respect. Just like we address, “Kirtanananda Maharaja.” Although he’s my disciple, but the respect should be given. Here, see, Narada is addressing Vyasadeva: “Prabhu.”

From Srila Prabhupada’s lecture on SB 1.5.1-4, May 22, 1969