Yoga redresses grief for one who is moderate in his food habit and recreation, moderate in his activity and rest, moderate in sleeping and waking.
This verse is an aphorism (sūktam) of Gita. Krishna emphasizes the principle of moderation as a watchword for all aspects and facets of life.
Yuktatā, integration and evenness, he says, is applicable to appeasing hunger as well as recreation, meaning walking and other activities. The object of eating is to provide nourishment to the body, so as to energize it to meet the wakeful needs. One is to be awake for about seventeen hours. For the remaining seven hours he is expected to sleep and recuperate his body.
Wakefulness and sleep are complementary. One has to be moderate in both, not allowing either to take over the other’s share. The same applies to activity and rest. Only for one of moderation, yoga is effective and fruitful.
Krishna does not enjoin any other condition to practise yoga. By this, he is making the Gita a way of life accessible to everyone in the world. What a great relief and blessing! How reassuring a promise!