After announcing the Kingdom of Heaven in the Sermon on the Mount, Jesus gives another speech in the Gospel of Matthew where he describes this Kingdom through 7 mysterious parables. And some of these parables are the most famous parables of Jesus, the parable of the sower, the parable of the yeast, and the parable of the treasure.
For common and simple people most of the parables are incomprehensible, but Jesus wants to give us these stories or tales to introduce us to the most important characteristics of this new Kingdom: growth, development, inner transformation, self-knowledge, which are some of the keys to the spiritual mystery of Jesus. It is important to emphasize that the parables of Jesus cannot be understood in the light of human reason, but rather through the gift of fear of God. This gift is the basis of all human spirituality: "Fear God, and keep his commandments: for this is the whole duty of man", Ecclesiastes 12:13. Without saying it directly, the parables are actually a complement to the golden rule, the characteristics of the Kingdom are also the characteristics of the righteous life: "Do unto others as you would have them do unto you", Matthew 7:12.
And Jesus after finishing his speech asked the crowd:
"´Have you understood all these things?´Jesus asked.
´Yes,´ they replied.
He said to them, ´Therefore every teacher of the law who has become a disciple in the kingdom of heaven is like the owner of a house who brings out of his storeroom new treasures as well as old´" Matthew 13:51-52.
The old and new treasures, in this explanation, are the teachings of the old and new testament, the parables are the summary of everything revealed by God to men from the very beginning of humanity to Jesus. Jesus enlightens us in the mysteries of wisdom.
Jesus asks us to be like that teacher of the law who is the conclusion of all the parables. Jesus wants us to retain both the old teachings and the new with a willing heart to enter into that new life that is eternal life: "This is eternal life that they know you the only true God" John 17:3.