The main purpose of the "Malleus Maleficarum", or "The Hammer Against Witches", was to refute all arguments that witchcraft did not exist, refute those who were skeptical about its reality, to prove that witches were more often women than men, and to educate magistrates on the how to find witches and convict them.
This book reflects that Sprenger and Kramer not only severely lacked a sense of humor and were obsessed with sex, but also that they had major issues with women; the book singles women out as the weaker sex, weaker in faith, lustful and easy by nature, and thus easy prey for Satan's coaxing. The men even went so far as to state the etymology of "femina" (Latin for "woman") as "fe" ("faith") + "minus" ("less"), which it is not.
Indeed, the book uses the exclusively feminine "malefica" rather than the masculine (and more inclusive) "maleficus" to denote witches, a strong implication that only women were witches in their eyes. Also, Sprenger and Kramer stated that old women and Jews were most likely witches and should never be trusted.
The Malleus Maleficarum accuses witches of cannibalistic infanticide, casting evil spells to harm their enemies, and holding the power to steal men’s penises (even make them come to life). It goes on to give accounts of witches committing these crimes.
The Malleus also delves deeply into the Bible, astrology, and philosophy, as this book was published during the Renaissance.
This whole book is one long tirade not just against women, but also heretics, independent thinkers, romantic lovers, the sensitive passions, human sexuality, and compassion.
The reasoning and logic used are bewilderingly outlandish... as horrible as the the images and reasoning are, they are also so ridiculous that it would be funny if the subject matter were not so grim.
Amazingly, in its day, this book of intolerance and persecution was second most popular after the Bible.
Thousands of innocents were killed because of Sprenger and Kramer, because of the hysteria and paranoia that they sparked, eventually leading to the Burning Times.
-The Malleus Maleficarum
That sums up the tone of the book. Here's more:
"When a woman thinks alone, she thinks evil."
“For though the devil tempted Eve to sin, yet Eve seduced Adam. And as the sin of Eve would not have brought death to our soul and body unless the sin had afterwards passed on to Adam, to which he was tempted by Eve, not by the devil, therefore she is more bitter than death.” (Kramer, Question 6)
"She is a liar by nature."
"...they have slippery tongues... they are intellectually like children... she is more carnal than a man, as is clear from her many carnal abominations."
And on and on; it's basically the work of two sexually repressed, frustrated monks who were so alienated towards women that the only way that they could deal with women was to slander them. They basically claimed that women were frivolous, stupid, dirty, weak, emotionally unstable, faithless trollops who were up to no good.
Because of the Malleus Maleficarum, women could be accused to witchcraft because a few men had an erotic dream about her or because she made a correct prediction about the weather or some other mundane thing that could be logically explained.