Mt 13:10-13
10And the disciples came, and said unto him, Why speakest thou unto them in parables? 11And he answered and said unto them, Unto you it is given to know the mysteries of the kingdom of heaven, but to them it is not given. 12For whosoever hath, to him shall be given, and he shall have abundance: but whosoever hath not, from him shall be taken away even that which he hath. 13Therefore speak I to them in parables; because seeing they see not, and hearing they hear not, neither do they understand.
What is a parable?
In the literal sense, it is a curved line that loops to connect one point to another; but not only that, considering this line as a barrier, in the inner part, any wave that "hits" this line will be reflected in a central point called focus. That's why the satellite dish captures the signal at the center of the antenna, that is, every signal wave that hits the parabola is reflected to the same focus.
Putting it textually, parables are written to convey a specific message, with a focus. A narrative is written not to pass the message directly, but in a figurative way, with a return to send a message to those who can hear and hear, understand and use.
Why did Jesus speak in parables?
As He himself explained in Mt 13:11, the parables told by Jesus are so that only a few people, with enough discernment, can understand. They are messages for the children of the Kingdom of God, that is, who is a child has the knowledge, and has a heart prepared to understand this message. Those who are not children only understand the literal meaning of the interpretation of the text and not the real focus / reason for which the parable was told.