True concentration itself is free from such contaminants. It is a state in which the mind is gathered together and thus gains power and intensity. We might use the analogy of a lens. Parallel waves of sunlight falling on a piece of paper will do no more than warm the surface. But if that same amount of light, when focused through a lens, falls on a single point, the paper bursts into flames.
( Henepola Gunaratana )
[ Mindfulness in Plain English ]
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