The process of yoga is very clearly described in this verse of Srimad-Bhagavatam. It is said here that the ultimate end of the yogis and mystics who perform meditation is to get rid of this material body. Therefore they meditate in secluded places to attain yogic trance. Yoga has to be performed in a secluded place, not in public or in a demonstration on stage, as nowadays practiced by many so-called yogis. Real yoga aims at ridding one of the material body. Yoga practice is not intended to keep the body fit and young. Such advertisements of so-called yoga are not approved by any standard method. Particularly mentioned in this verse is the word yam, or unto whom, indicating that meditation should be targeted on the Personality of Godhead. Even if one concentrates his mind on the boar form of the Lord, that is also yoga. As confirmed in Bhagavad-gita, one who concentrates his mind constantly in meditation upon the Personality of Godhead in one of His many varieties of forms is the first-class yogi, and he can very easily attain trance simply by meditating upon the form of the Lord. If one is able to continue such meditation on the Lords form at the time of ones death, one is liberated from this mortal body and is transferred to the kingdom of God. This opportunity was given to the demon by the Lord, and therefore Brahma and other demigods were astonished. In other words, the perfection of yoga practice can be attained by a demon also if he is simply kicked by the Lord.