At one place, the Buddha has called the practice of mindfulness the one way to achieve the end of suffering. Specifically, the practice of mindfulness has been developed to include four particular applications. These four stations of mindfulness have continued to play an important role in the practice of Buddhist meditation. Let us go on to consider the third step, and that is concentration, or it is sometimes called meditation, or tranquillity. You will recall that we traced the origin of meditation all the way back to the Indus Valley Civilization.
Concentration has nothing to do with frenzy, or torpor, or semi-consciousness.
Concentration is the practice of focussing the mind single-pointedly on a single object. The object may be physical or mental. When total single-pointedness of the mind upon a single object is achieved through concentration, the mind is totally absorbed in the object to the exclusion of all thoughts, distractions, wavering, agitation, or drowsiness. This is the object of the practice of Right Concentration, to focus the mind single-pointedly upon one object. Most of us have had intimations of this state.