At a certain stage in your kriya yoga practice you may find that your mind becomes very calm, and only a few minor thoughts arise. At this point there is justification for suppression. This situation may arise after a few months of regular practice, or it may occur during a particularly auspicious practice session. You should definitely not suppress emotionally charged thoughts, but minor ones can be ‘squashed’. It is like an elephant and an ant. If an elephant annoys you and disturbs your peace, tact must be used. You have to watch carefully and use cunning to get rid of the elephant. If an ant annoys you, on the other hand, then it can be quickly picked up and removed. It is the same with major and minor thoughts. You must use your discretion here in deciding which thoughts are minor in nature.
Wakefulness and sleepiness
One of the biggest problems in kriya yoga practice is sleepiness. There is a tendency in human nature to easily sink into the state of slumber, especially if there is some mental relaxation, such as will arise during kriya yoga practice. Many people want this drowsiness, for it is pleasant and allows one to forget the problems of daily life. But you should try to understand that the state of meditation, attained through relaxed wakefulness, is far more pleasant. Furthermore, relaxed wakefulness leads to self-knowledge and bliss, whereas sleep, even ten years of continuous sleep, will never result in self-knowledge. Therefore, the serious practitioner should make all efforts to remain wide awake throughout the practice, no matter how tempted he is to gently slip into a state of sleep and pleasant dreams. It is far better to do kriya yoga with a wandering mind than a sleeping mind, for at least the problems of the mind can be removed if there is wakefulness.
In kriya yoga, you should try to remove the tamasic state by taking a cold bath, doing some asanas and surya namaskara beforehand, and making a resolve that you will not sleep. The rajasic state is absolutely necessary; it is the state where the mind is emptied of thoughts and progressively harmonized; you must try to be aware of the process. This awareness will eventually lead to the sattwic state and meditation.