It is impossible to practice concentration of the mind unless the mind is purified, that is, made peaceful in nature. The best way for this shown in yoga philosophy. It is the way of cultivating the attitude of friendliness, compassion, gladness and indifference in respect of people or events which are causing happiness, misery, virtue or vice. By maintaining this attitude, that is, friendliness to the happy ,compassion for the unhappy, gladness about the virtuous and indifference to those who are full of vice, the mind of the aspirant becomes free from disturbing influence and as result it become peaceful and undisturbed . The process of introversion follows easily. The mind by nature is full of unrest, like pond that disturbed by the falling of objects like boulders boulders, stones, etc. The unsteady mind cannot become concentrated easily. As we know the nature of the mind has a tendency to be attracted towards the outside world. It is not in the nature of the mind to look within.Therefore, when you are trying to turn the mind inside, the obstacles and impurities must be first removed. Jealously, hate and the element of competition cause a lot of impurities in the mind. When we see a happy and prosperous person, we feel jealous. This causes a disturbance in the subconscious mind and obstructs the mind from being concentrated. The results in fearful visions. When we come across a person suffering, we enjoy it if he happens to be an enemy. This is also one of the impurities of the mind. Similarly, we often criticize virtuous persons and hail the deeds of vicious person. All this causes disturbance in the mind and comes in the way of peace and meditation.
In yoga philosophy has shown a way of overcoming these disturbances. The fourfold attitude which he ask us to develop gives rise to inner peace by the removal of the disturbing factors, not only from the conscious level, but also from the deepest parts of the subconscious.