Matthew 13:31-35

31He gave them another parable [to consider], saying, “The kingdom of heaven is like a mustard seed, which a man took and sowed in his field;

32and of all the seeds [planted in the region] it is the smallest, but when it has grown it is the largest of the garden herbs and becomes a tree, so that the birds of the air find shelter in its branches.”

33He told them another parable, “The kingdom of heaven is like leaven, which a woman took and worked into three measures of flour until all of it was leavened.”

34All these things Jesus said to the crowds in parables, and He said nothing to them without [using] a parable.

35This was to fulfill what was spoken by the prophet: “I will open My mouth in parables; I will utter things [unknown and unattainable] that have been hidden [from mankind] since the foundation of the world.”