It is very difficult subject matter. It is not possible for ordinary man. The first principle is that he has to sit down alone in a sacred place, alone. yoga practice is not possible in a big city, with friends and smoking habit and drinking habit. This all farce. One has to become very strong in controlling the mind, controlling the senses, sitting in a solitary place, sacred place like Himalaya or Haridwar, like that. And who is going there, and who is practicing? It is not possible. Not only that—he has to sit down straight, and not bending, and looking on the tip of the nose, and not closing the eyes completely, half closed—so many rules and regulation—and always thinking of Viṣṇu. Dhyānāvasthita-tad-gatena manasā pra . . . (SB 12.13.1). It is not possible. This yoga system, Arjuna denied five thousand years ago. And what we are? This is going on, all farce.
Here is the yoga system Kṛṣṇa is describing, sa ma guhyatamam, most confidential yoga system. What is that? Man-manā bhava mad-bhakto (BG 18.65): "Simply always think of Me." Man-manā. Mad-bhakta: "You just become My devotee." So this chanting of Hare Kṛṣṇa mantra is always thinking of Kṛṣṇa. Even I don't like it think Kṛṣṇa, as soon as the name is chanted immediately I'm forced to think of Kṛṣṇa, immediately. Hare Kṛṣṇa, as I say, immediately I remember Kṛṣṇa, man-manā.
Not only that; a devotee thinks of Kṛṣṇa because he develops love for Kṛṣṇa. And as soon as we develop our love for Kṛṣṇa, we must have to think of Kṛṣṇa. Just like we think of our lover, beloved, always; similarly, by chanting Hare Kṛṣṇa mantra we develop our love for Kṛṣṇa. Therefore as soon as I chant Hare Kṛṣṇa, I immediately remember Kṛṣṇa. That is man-manā. And unless I have developed devotional service, then how I can chant Kṛṣṇa? Just like they are chanting Hare Kṛṣṇa. But I am advising everyone. But we, who others are chanting, they are not chanting, because they have no love for Kṛṣṇa. Ah.
So man-manā bhava mad-bhakto mad-yājī (BG 18.65). And how it is prac . . . how it is? By worshiping Kṛṣṇa. Just like we have got our temple, Rādhā-Kṛṣṇa temple, and from morning, four o'clock, to night ten o'clock, they have got business how to worship Kṛṣṇa. This time ārati, this time bhoga, this time chanting, this time reading about Kṛṣṇa, understanding about Kṛṣṇa—whole day and night we have got prescription. If you come to our temple in the foreign countries, you'll be pleased to see how they are doing.