Matthew 13:31-35

He told them another parable: ‘The kingdom of heaven is like a mustard seed, which a man took and planted in his field. Though it is the smallest of all seeds, yet when it grows, it is the largest of garden plants and becomes a tree, so that the birds come and perch in its branches.’ He told them still another parable: ‘The kingdom of heaven is like yeast that a woman took and mixed into about thirty kilograms of flour until it worked all through the dough.’ Jesus spoke all these things to the crowd in parables; he did not say anything to them without using a parable. So was fulfilled what was spoken through the prophet: ‘I will open my mouth in parables, I will utter things hidden since the creation of the world.’