The Lord gives guidelines in this verse and the following ones on the possible pitfalls that have to be guarded against in pursuit of meditation. The central theme of His guidance is that moderation in all activities at all levels is the precondition for achieving success in Meditation. Intemperateness in any field of behavior and activity brings about mental agitations which are not conducive to the development of an integrated personality.

Therefore moderation in food, sleep and recreation is directed.

Yoga is not possible for him who eats too much nor for him who does not eat at all. Eating means not only the process of consuming food but includes enjoyments gained through all means of sense perceptions and inward experiences. Similarly, neither too much sleep which erodes the faculties nor lack of sleep which disturbs the body rhythm is advised for spiritual life. Everything in moderation is the rule.

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(Tu, but) O Arjuna, Yoga na asti, is not; atiasnatah, for one who eats too much, for one who eats food more than his capacity; na ca, nor is Yoga; anasnatah, for one who does not eat; ekantam, at all. This accords with the Vedic text, ‘As is well known, if one eats that much food which is within one’s capacity, then it sustains him, it does not hurt him; that which is more, it harms him; that which is less, it does not sustain him’ (Sa. Br.; Bo. Sm. 2.7.22). Therefore, a yogi should not eat food more or less than what is suitable for him. Or the meaning is that Yoga is not for one who eats more food than what is prescribed for a yogi in the scriptures on Yoga. Indeed, the quantity has been mentioned in, ‘One half of the stomach is to be filled with food including curries; the third quarter is to be filled with water; but the fourth quarter is to be left for the movement of air,’ etc. Similarly, Yoga is not for ati svapna-silasya, one who habitually sleeps too long; and Yoga is na eva, surely not; jagratah, for one who keeps awake too long. How, again, does Yoga become possibel? This is being stated: