Uncontrolled thoughts are the roots of all evils. Each thought by itself is extremely weak, because the mind is generally distracted by countless and ever-varying thoughts.
The more the thoughts are restrained, the more is the mind concentrated, and consequently the more does it gain in strength and power.
It demands patient work to destroy mean and base thoughts; but the entertainment of sublime thoughts is the easiest and most rapid method of destroying base thoughts. Ignorant of the laws of thoughts, the worldly-minded individual falls a prey to all sorts of thoughts - thoughts of hatred, anger, revenge, lust - and grows weak-willed, deficient in the powers of discernment, and slave of the adverse subtle workings of the mind.
The best method of gaining mental power is by entertaining sublime, noble and good thoughts and through their aid controlling the dissipative, distractive, diversifying, worldly and base thoughts.
When all evil thought harasses the mind, the best method of conquering it is by ignoring it. How can we ignore an evil thought? By forgetting it. How can we forget? By not indulging in it again, and also by not brooding over it.
How can we prevent the mind from indulging in it again or brooding over it? By thinking of something very interesting, something sublime and inspiring. Ignore, forget, think of something inspiring; these three constitute the great Sadhana for establishing mastery over evil thoughts.
-- Swami Sivananda in "Thought Power"
SEED QUESTIONS FOR REFLECTION: What has been an effective method of conquering evil thoughts for you? The author emphasizes patient work - what is your reflection on the need for patience in the quest to gain mastery of our minds? Can you share a personal story that illustrates an experience of focusing on the good while refusing to give attention to evil thoughts?