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What difference is there between seeing and looking, between hearing and listening? A person absorbed in his thoughts may hear a conversation going on but be absolutely unaware of it, his attention is fixed on something else He hears the sounds reach his ears, but he is not listening.
The same occurs with seeing and looking. We constantly see lots of things around us and yet they pass before our eyes unnoticed, as if they were not occurring. In others words, we do not look, we do not pay attention to them In this case also our mind is elsewhere.
Attention, then, is what makes the difference between hearing and listening, between seeing and looking. Those who sees but do not look, and hear but do not listen, are those who do not pay attention to what is occurring before their eyes or ears.
There are time when our attention is caught automatically by what we see or hear, our eyes and ears are attracted by pleasing images and sounds the way iron is attracted by magnet. But this kind of looking or listening is more passive than active, our attention is caught because it is attracted and our will, our desire, expresses itself in a negative manner by not rejecting the thing. We can say if there is attention it is because something pleases us, not because it really interests us. This kind of thing happens at lectures if the speaker is able to present his subject with enough skill to capture our attention.
The disciples had enough interest in our Lord's words at least that is how i see it to ask and learn what the words meant. The rest of his listeners, however, did not care one way or the other about the message his words contained. The pharisees choice of a closed mind was simply the expression of their voluntary rejection of Jesus message, because they did understand it on several occasions, and the fact of disputing with him is proof of this.
This explains why only the disciples, but not the rest,were granted to know the mysteries of the kingdom of heaven. Among all his listeners, they were the only ones who asked the Lord, the only ones who showed interest to inquire what he really meant by that parable. They alone showed a desire to learn, and we all must try to listen more to the words of our Lord just as the disciples did.