The purification of the instruments of knowing are the basis for the development of concentration. Ordinarily, the objects of the senses impinge upon our awareness and we are drawn out towards them in a number of directions. The promptings of desire further distract us, so that our minds are constantly in flux and dispersed. When we begin the practice of meditation, we find that there are thoughts and impressions jumping about and pulling our attention in all directions. There are moments when we fixate our attention on some specific idea or project and we call that concentration; however, this concentration on some outer form or idea is not the intense concentration required to achieve the divine standpoint of consciousness.
Sri Aurobindo observes: “…we have to fix the will and the thought on the eternal and real behind all, and this demands an immense effort, a one-pointed concentration. Secondly, it is necessary in order to break down the veil which is erected by our ordinary mentality between ourselves and the truth; for outer knowledge can be picked up by the way, by ordinary attention and reception, but the inner, hidden and higher truth can only be seized by an absolute concentration of the mind on its object, an absolute concentration of the will to attain it and, once attained, to hold it habitually and securely unite oneself with it. For identification is the condition of complete knowledge and possession; it is the intense result of a habitual purified reflecting of the reality and an entire concentration on it; and it is necessary in order to break down entirely that division and separation of ourselves from the divine being and the eternal reality which is the normal condition of our unregenerated ignorant mentality.”
Sri Aurobindo, The Synthesis of Yoga, Part Two: The Yoga of Integral Knowledge, Chapter 25, The Higher and the Lower Knowledge, pg. 494