Yoga as Meditation on Kṛṣṇa
19
and one executes this system properly, then he can control his mind. After one has met  all  the requirements for meditation, he must transfer his whole thought to Kṛṣṇa or Viṣṇu. It is not that one is to transfer his thought to vacancy. Thus Kṛṣṇa says that one absorbed in the meditational  yoga  system is “always thinking of Me.”
The  yogī  obviously has to go  through  a great  deal  of difficulty to purify the  ātmā  (mind, body and soul), but it is a fact that this can be done most effectively in this age simply by the chanting of Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare. Why is this? Because this transcendental sound vibration is nondifferent from Him. When we chant His name with devotion, then Kṛṣṇa is with us, and when Kṛṣṇa is with us, then what is the possibility of remaining impure? Consequently, one absorbed in Kṛṣṇa consciousness, in chanting the names of Kṛṣṇa and serving Him always, receives the benefit of the highest form of  yoga . The advantage is that he doesn't have to take all the trouble of the meditational process. That is the beauty of Kṛṣṇa consciousness.
In  yoga  it is necessary to control all of the senses, and when all the senses are controlled, the mind must be engaged in thinking of Viṣṇu. One becomes peaceful after thus conquering material life.
jitātmanaḥ praśāntasya paramātmā samāhitaḥ śītoṣṇa-sukha-duḥkheṣu tathā mānāpamānayoḥ