Jesus said to the crowds: “This is how it is with the kingdom of God; it is as if a man were to scatter seed on the land and would sleep and rise night and day and through it all the seed would sprout and grow, he knows not how. Of its own accord the land yields fruit, first the blade, then the ear, then the full grain in the ear. And when the grain is ripe, he wields the sickle at once, for the harvest has come.”
He said, “To what shall we compare the kingdom of God, or what parable can we use for it? It is like a mustard seed that, when it is sown in the ground, is the smallest of all the seeds on the earth. But once it is sown, it springs up and becomes the largest of plants and puts forth large branches, so that the birds of the sky can dwell in its shade.”
With many such parables he spoke the word to them as they were able to understand it. Without parables he did not speak to them, but to his own disciples he explained everything in private.
Mark 4:26-34