[At Saavatthii the Brahman Sangaarava asked the Buddha:] "Why is it, good Gotama, how does it come about that sometimes sacred words[1] I have long studied are not clear to me, not to mention those I have not studied? And how is it too that sometimes other sacred words that I have not so studied are clear to me, not to mention those I have studied?"
"Well, Brahman, when a man dwells with his heart possessed and overwhelmed by sense-desires, and does not know, as it really is, the way of escape from sense-desires that have arisen, then he cannot know or see, as it really is, what is to his own profit, nor can he know and see what is to the profit of others, or of both himself and others. Then even sacred words he has long studied are not clear to him, not to mention those he has not studied.
"Imagine, Brahman, a bowl of water mixed with lac, turmeric, dark green or crimson dye. If a man with good eyesight were to look at the reflection of his own face in it, he would not know or see it as it really was. In the same way, Brahman, when a man dwells with his heart possessed and overwhelmed by sense-desires... then he cannot know or see, as it really is, what is to his own profit, to the profit of others, to the profit of both. Then even sacred words he has long studied are not clear to him, not to mention those he has not studied.
"Again, Brahman, when a man dwells with his heart possessed and overwhelmed with ill-will... then he cannot know or see...
"Imagine a bowl of water, heated on a fire, boiling up and bubbling over. If a man with good eyesight were to look at the reflection of his own face in it, he would not know or see it as it really was...
"Again, Brahman, when a man dwells with his heart possessed and overwhelmed by sloth-and-torpor... then he cannot know or see...
"Imagine a bowl of water covered over with slimy moss and water-plants. If a man with good eyesight were to look at the reflection of his own face in it, he would not know or see it as it really was...
"Again, Brahman, when a man dwells with his heart possessed and overwhelmed by worry-and-flurry... then he cannot know or see...
"Imagine a bowl of water ruffled by the wind, so that the water trembled, eddied and rippled. If a man with good eyesight were to look at the reflection of his own face in it, he would not know or see it as it really was...
"Again, Brahman, when a man dwells with his heart possessed and overwhelmed by doubt-and-wavering... he cannot know or see...
"Imagine a bowl of water, agitated, stirred up muddied, put in a dark place. If a man with good eyesight were to look at the reflection of his own face in it, he would not know or see it as it really was. In the same way, Brahman, when a man dwells with his heart possessed and overwhelmed by doubt-and-wavering... then he cannot know or see, as it really is, what is to his own profit, to the profit of others, to the profit of both. Then even sacred words he has long studied are not clear to him, not to mention those he has studied. But, Brahman, when a man dwells with his heart not possessed, not overwhelmed by sense-desires... ill-will... sloth-and-torpor... worry-and-flurry... doubt-and-wavering... [like the five bowls of water not as previously described, but 'clear, limpid, pellucid, set in the open']... then he knows and sees, as it really is, what is to his own profit, to the profit of others, to the profit of both himself and others. Then even sacred words he has not long studied are clear to him, not to mention those he has studied."