The activity of mind can be recognized in three different aspects, mobile, rhythmic and chaotic. And the activity of mind can be seen by the speech and action of a person.

If, in speech and action a person shows a friendly attitude, love and kindness, the activity is mobile, and every impulse prompted by this activity will manifest in the form of gentleness, generosity, gratitude and goodwill.
If the activity of mind is rhythmic it will make a person more reasoning. He will be exacting, weighing, measuring, loving and hating; liking and dislike will be balanced. This is not an easy-going person; this person will be more businesslike. All that manifests from him in speech or action will be more substantial, reasonable, also progressive in a worldly sense.
But the person the activity of whose mind is chaotic will be agitated, confused, suspicious, horrified, and all that will manifest in his speech and action will be anger, passion, intolerance, imprudence, and will be difficult for himself and for others.

No soul is by nature fixed to any of these three aspects of activity; it is what he allows himself to be or what the condition of his life makes him be. Therefore the principle of Sufi teaching is to regulate the rhythm of man's mind. Then the Sufi becomes the master of the rhythm of his own mind, his mind becomes his instrument. He can play on it any music of any rhythm and nothing will affect it, for he is no longer in the hand of his mind, his mind is in his hand.