The parables have a double use, to vail and to illustrate, to teach and to conceal.
To show people that the only true fruit of good teaching is holiness of life, and that there were many dangers which might prevent its growth, Jesus told them His first parable, the Parable of the Sower.(Luke 8). The imagery of it was derived, as usual, from the objects immediately before His eyes - the sown fields of Gennesareth; the springing corn in them; the hard-trodden path which ran through them, on which no corn could grow; the innumerable birds which fluttered over them ready to feed upon the grain; the weak and withering struggle for life on the stony places; the tangling growth of luxuriant thistles in neglected corners; the deep loam of the general soil, on which already the golden ears stood thick and strong, giving promise of a sixty and hundred- fold return as they rippled under the balmy wind.
We see in this parable the liveliest images of the danger incurred by the cold and indifferent, by the impulsive and shallow, by the worldly and ambitious, by the preoccupied and the luxurious, as they listen to the Word of God. (Dean Farrar)