The Importance of Praiogenam

One of the great Swami's of our order long before my time, Swami Bhashkareshwarananda. He was a great teacher of Advaita of Vedanta and established our ashram in Nagpur. How he would begin a class on the Gita: "Keep this by praiogenam vibrating within you" And these are just two sentences from his notes; I have never attended those classes.