SB 4.24.71
yogadesam upasadya
dharayanto muni-vratah
samahita-dhiyah sarva
etad abhyasatadrtah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
My dear princes, in the form of a prayer I have delineated the yoga system of chanting the holy name. All of you should take this important stotra within your minds and promise to keep it in order to become great sages. By acting silently like a great sage and by giving attention and reverence, you should practice this method.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
In the hatha-yoga system one has to practice bodily exercises, dhyana, dharana, asana, meditation, etc. One also has to sit in one place in a particular posture and concentrate his gaze on the tip of the nose. There are so many rules and regulations for the hatha-yoga system that it is practically impossible to perform it in this age. The alternative system of bhakti-yoga is very easy not only in this age but in others as well, for this yoga system was advocated long ago by Lord Siva when he advised the princes, the sons of Maharaja Pracinabarhisat. The bhakti-yoga system is not newly introduced, for even five thousand years ago Lord Krsna recommended this bhakti-yoga as the topmost yoga. As Krsna tells Arjuna in Bhagavad-gita (6.47):
yoginam api sarvesam
mad-gatenantaratmana
sraddhavan bhajate yo mam
sa me yuktatamo matah
“Of all yogis, he who always abides in Me with great faith, worshiping Me in transcendental loving service, is most intimately united with Me in yoga and is the highest of all.”
The topmost yogi is he who constantly thinks of Krsna within himself and chants the glories of the Lord. In other words, this system of bhakti-yoga has been existing from time immemorial and is now continuing in this Krsna consciousness movement.
The word muni-vratah is significant in this regard because those who are interested in advancing in spiritual life must be silent. Silence means talking only of krsna-katha. This is the silence of Maharaja Ambarisa:
sa vai manah krsna-padaravindayor
vacamsi vaikuntha-gunanuvarnane
“King Ambarisa always fixed his mind on the lotus feet of the Lord and talked of Him only.” (Bhag. 9.4.19) We should also take this opportunity in life to become as good as a great saint simply by not talking unnecessarily with unwanted persons. We should either talk of Krsna or chant Hare Krsna undeviatingly. This is called muni-vrata. The intelligence must be very sharp (samahita-dhiyah) and should always be acting in Krsna consciousness. The words etad abhyasatadrtah indicate that if one takes these instructions from a spiritual master with great reverence (adrta) and practices them accordingly, he will find this bhakti-yoga process to be very, very easy.