There is no one soo bad that God is wont willing to Change

George Whitefield, the famous British travelling preacher in 1700's England/America, preached several times a day before thousands, but some would laugh and mock.
At Rotherham some men met in a tavern, making bets to see who could best mimic his sermons. Each had to stand on a table, open the Bible and pretend to preach like Whitefield, while the others laughed.
One named Thorpe was the last to act. He jumped onto the table saying, "I will beat you all." He opened the Bible and read the first verse he saw, "Except ye repent, ye shall all likewise perish."(Luke 13:3) Suddenly he realised the solemn truth of the text, and was deeply convicted of his lost condition. He tried to preach, but instead of mocking, he spoke very seriously. A solemn quietness spread over the whole group, and those who'd come to scoff went away in tears.
Thorpe was saved by the Lord, later laboring for many years as a faithful preacher of the gospel.