The Upanishads prescribe certain sadhanas (spiritual exercises) to achieve inner peace. One of that is engaging in Karma or beneficial activity - that is to say, service to people which will help diminish the sense of ego; this refers to acts that are good and godly. When one’s thoughts are engaged in such activities, the mind turns away from the talk it indulges in. Listening to spiritual advice, reflection on spiritual directions, and discovering ways and means of confirming faith in the Lord, recital of the names of God and withdrawing the mind from sensual pursuits have been prescribed by the scriptures for silencing the mental chatter, this inner talk, as a preparation for attaining the Supreme Lord. For it is only when the mind is cleansed and clarified that it can achieve such a profound task. Only then the lessons taught and the experiences undergo ne can be pure and unsullied.