The Parable of the Sower and the Seed as told by Jesus to make us aware that there is good and evil in his visible kingdom throughout the entire age.
Among those who profess his name there will be apostasy and worldliness as well as faithfulness and godliness.
This parable, like most of the others are intended to alert his true disciples to expect evil within the kingdom and to teach them how to overcome the influence and opposition of Satan and his followers.
This parable is a story from everyday life that illustrates spiritual truths hidden in plain view for those who love God and are the called according to his purpose.