Fire and brimstone is a pejorative term used to describe a motif in Christian preaching which uses vivid descriptions of judgment, and the damnation to Hell of sinners forever to encourage repentance out of fear of divine wrath and punishment.
The Puritan preacher Thomas Vincent (an eyewitness of the Great Fire of London) authored a book called "Fire and Brimstone in Hell", first published in 1670. In it he quotes from Psalm 11:6 "Upon the wicked he shall rain snares, fire and brimstone, and a horrible tempest, this shall be the portion of their cup."