The Catechism in Questions & Answers

150. How did Jesus make the gospel understandable?

In His sermons, Jesus often spoke in parables, which are figurative narratives. These stories are taken from the daily lives of His listeners so that they might better understand them. With these parables, Jesus illustrated the main content of the gospel.
More than 40 parables are recorded in the first three gospels.

“All these things Jesus spoke to the multitude in parables; and without a parable He did not speak to them, that it might be fulfilled which was spoken by the prophet, saying ‘I will open My mouth in parables; I will utter things kept secret from the foundation of the world’.”
Matthew 13: 34-35