The Book of the Holy Scourge was a sacred book of the Church of Ilmater. Though not the holiest book of the faith (that honor went to the Tome of Torment), it was probably the most well-known and useful by 1370 DR.
Thieves once stole the Book of the Holy Scourge and attempted to sell it. In response, no less than twenty high priests of the church, from all across Faerûn, appeared by magic and hurled killing spells at the thieves. Despite their own great power and a hard fight, the thieves were slain.