(And as soon as the heart is cleansed of all dirty things, material contamination, then we can see what is our relationship with Kṛṣṇa. Therefore, Kṛṣṇa recommends that "Somehow or other, you try to be attached to Me.") 
That is called svarūpa-siddhi. How we are . . . how I am related with Kṛṣṇa, that will be revealed. I have got a relationship with Kṛṣṇa eternally. Now it is covered. So practice this yoga means reviving our original relationship with Kṛṣṇa. In the Caitanya-caritāmṛta it is said:
nitya-siddha kṛṣṇa-prema 'sādhya' kabhu nayaśravaṇādi-śuddha-citte karaye udaya(CC Madhya 22.107)
It is simply awakened. Not that artificially we are imposing some impression to the minds of our students that they are hankering after "Kṛṣṇa, Kṛṣṇa, Kṛṣṇa." No. It is a process to remove all the dirty things from the heart. Ceto-darpaṇa-mārjanam (CC Antya 20.12).
And as soon as the heart is cleansed of all dirty things, material contamination, then we can see what is our relationship with Kṛṣṇa. Therefore, Kṛṣṇa recommends that "Somehow or other, you try to be attached to Me." And the Gosvāmīs also, Rūpa Gosvāmī recommends, yena tena prakāreṇa manaḥ kṛṣṇe niveśayet (Brs. 1.2.4): "Somehow or other, try to apply your mind in Kṛṣṇa."
(His Divine Grace A.C.Bhaktivedanta Swami Srila Prabhupada Lecture, March 28, 1971, Bombay)
Comments
"As spirit soul we are free, sarva-ga. We can go everywhere, anywhere. Even those who get some mystic powers by perfection of yoga practice, they can also exhibit some powers. So why? As we become free from material conditions, our original freedom comes.
So one of the qualification of the spirit soul is sarva-ga. Sarva-ga means he can go anywhere and everywhere. Nārada, because he is free, he has got full spiritual body, he can go anywhere he likes."
(His Divine Grace A.C.Bhaktivedanta Swami Srila Prabhupada Lecture, March 28, 1968, San Francisco)