Heinrich Kramer & Jacob Sprenger 
Malleus Maleficarum [EPUB ebook] 

The Malleus Maleficarum , usually translated as the
Hammer of Witches , is the best known treatise purporting to be about witchcraft. It was written by the German Catholic clergyman
Heinrich Kramer (under his Latinized name Henricus Institor) and first published in the German city of Speyer in 1486. Some describe it as the compendium of literature in demonology of the 15th century. Kramer blamed women for his own lust, and presented his views as the Church’s position. The book was condemned by top theologians of the Inquisition at the Faculty of Cologne for recommending unethical and illegal procedures, and for being inconsistent with Catholic doctrines of demonology.
The Malleus calls sorcery heresy, which was a crime at the time, and recommends that secular courts prosecute it as such. The Malleus suggests torture to get confessions and death as the only certain way to end the ‘evils of witchcraft.’ When it was published, heretics were often sentenced to be burned alive at the stake and the Malleus suggested the same for ‘witches.’ Despite, or perhaps because of, being condemned by the church, the Malleus was popular for a time among laypeople.
In 1519, a new author was added, Jacob Sprenger. Historians have questioned why since this was 33 years after the book’s first printing, and 24 years after Sprenger died. Kramer wrote the Malleus after he was expelled from Innsbruck by the local bishop. Kramer was accused of illegal behavior, and the tribunal was suspended because of Kramer’s obsession with the sexual habits of the accused, Helena Scheuberin: the papal bull Summis desiderantes affectibus which formed the basis of the investigation permitted the investigation of heresy, not sexual impropriety.
The book was later revived by royal courts during the Renaissance, and contributed to the increasingly brutal prosecution of witchcraft during the 16th and 17th centuries.