Only thus can he prevent the mind from wandering away from the object of concentration. This should be followed by concentration on a suitable spiritual centre within the body. The Sadhak may concentrate with closed eyes on the space between is the eyebrows or on the tip of the nose. There is nothing which cannot be achieved by concentration. Concentration should be followed by meditation.
Meditation is nothing but protracted or sustained concentration.
A scientist has to concentrate on a problem, on a given subject, on a riddle, to bring out the answer, to solve it. He has to think, think and think. Then only the answer flashes forth. Likewise, meditation is intense concentration, concerted concentration on the problem of life, on the problem of the inexplicable triad of God, man and the universe. Meditation can be practised on any image of the Lord.