Jesus did not tell parables to confirm well-known truths, but rather to shatter well-known truths.
From John 8:31-32: “Then Jesus said to the Jews who had believed in Him, ‘If you continue in My word, you are truly My disciples, and you will know the truth, and the truth will make you free.'”
John Newton (1725-1807) was an English pastor who also was a writer of several hymns, including the beloved “Amazing Grace.” His early life is filled with contrasts, when compared to his later life. He served as a ship’s captain during the slave trade, but later renounced his work after his conversion to Christianity. He became an outspoken opponent of the slave trade later in his life.