Matthew 15: 10
Then he called the crowd to him and said to them, "Hear and understand..." [and then he relates a parable of particular importance. It is of such importance that Peter says:]
Matthew 15: 15
But Peter spoke to him, saying "Explain to us this parable."
You can see here just one of many examples where Jesus not only calls attention of the Apostles to an important parable, so they will hear, understand and later recall, but the crowd too, in the first place! Jesus structured what he said, taught and did in the short amount of time of his public ministry so that people who were used to relying on memory, and had no texts but the Torah in the synagogues, could be alerted to his saying something important that should be understood and recalled.
I'll add other examples as I come across them, but now you know to be alert to them. When Jesus said things like "hear and understand," this was not to be dramatic in speech. It was to give an alert to people who were 1) entirely dependent on the oral word and memory 2) those who would follow him, evangelizing and teaching the word that he was about to say something that they needed to give their full attention to hearing, understanding and remembering. There was absolutely nothing like notepads or a way to "jot something down," and once he said something, he had to move on and people needed to understand it when it was first said. So you can read the Gospels with new eyes, alert to how Jesus provides in advance a structure to what the Apostles and disciples will recall, share and explain on their own after him...
St. Luke 8:8-9
... As he said these things he cried out, "He who has ears to hear, let him hear!"
But his disciples then began to ask him what this parable meant.
[Here Jesus does this same formula of alerting the crowd of a particularly important parable to remember, and thus also the disciples, who prick up their ears even more and as Peter did in the previous passage, question him more closely to be sure to understand. This particular parable is of such importance among importance that Jesus completes his explanation of the parable with another reminder of the importance of listening and retaining/recalling and correctly understanding what he says.]
St. Luke 8:18
"Take heed, therefore, how you hear; for to him who has shall be given; and from him who does not have, even what he thinks he has shall be taken away."
[This is a very important example of not only highlighting the parable itself and its meaning, but also the importance of correct hearing and "mental processing" of what you hear. With these words Jesus is doing a "wrap" of his explanation of the parable, which deals with how to retain what you receive. for the parable is about how to retain your faith once you have received it. But Jesus neatly summarizes the message of the parable (that you might receive faith but through circumstances or loss of care might lose it) by also giving a lesson in how to hear what he is saying. Jesus says to take heed "how you hear." It is important to not only hear something but to hear it correctly and using correct technique, in a manner of speaking. If you hear something properly ("him who has") then you will be given more because you are receptive to being a proper wisdom receiver and retainer. But someone who listens improperly ("him who does not have") actually ends up losing knowledge if he is listening wrongly to what he is being told. We've all had experiences where we are more confused by what someone said than before they spoke. In a way this is what Jesus is warning against, but he is saying that people have a responsibility for listening properly (you could say, listening with good will and intentions). But there is also, per the parable itself, a grace and skills level component. Jesus is teaching that proper listening must be the responsibility of the hearer, because those who properly listen can soak in and gain knowledge, while those who improperly listen to the same thing as the one who listens properly actually loses knowledge and the gifts of it in the process of the imperfect and flawed listening. So even if you think you know something, if you listen to it improperly and thus "process it" in a flawed way, you actually lose knowledge in the process. The parable itself was about this danger in the gaining and losing of faith itself. In a way Jesus is given both a theological lesson and a "listening technique" lesson, using the same words. This is why he opened with the statement about "having ears." Again it is not drama, or an artistic expression, but to highlight the focus and import of what he is about to teach, so that it can be properly recalled and practiced.]