Of mustard seeds and yeast

Jesus proposed a parable to the crowds. “The Kingdom of heaven is like a mustard seed that a person took and sowed in a field. It is the smallest of all the seeds, yet when full-grown it is the largest of plants. It becomes a large bush, and the ‘birds of the sky come and dwell in its branches.’”

He spoke to them another parable. “The Kingdom of heaven is like yeast that a woman took and mixed with three measures of wheat flour until the whole batch was leavened.”
All these things Jesus spoke to the crowds in parables. He spoke to them only in parables, to fulfil what had been said through the prophet: I will open my mouth in parables, I will announce what has lain hidden from the foundation of the world. (Mt 13, 31-35)

Jesus often delivered his teaching through short stories he told that were normally inspired by real life events. He did not speak in parables so as to hide truths from the uninitiated, or those who were not his followers. He was teaching the crowds, and he wanted them to understand his message. However, a little earlier Jesus told his disciples: “The reason I speak to them in parables is that ‘seeing they do not perceive, and hearing they do not listen, nor do they understand.’ The stories he told were quite simple but only those who were ready to listen could understand them. In some cases Jesus ended his stories saying: “Let anyone with ears listen!” Those who found it difficult to understand but really wanted to, asked Jesus to explain his parable and, as a good teacher, he did.