Obviously, the origin of “occult” magic was the pre-Christian practice of calling directly on the old gods with prayers and charms. In a sense, the “occult” stage of magic in the medieval period represents a time in which the old gods were no longer relevant and the worldview of the magicians was entirely Christian. The Bible stated that prayers to God might or might not prevail, but faith to keep believing when things ran against your interests was too much to ask of some. These people wanted a way to make things turn out right: heal the sick, stop the drought, win back love. Natural magic went only so far. When the outcome counted most, it was time to turn to something forbidden that really worked.
That’s always been the main pitch for occult magic: hey, it works. You may not approve of using blood to call on spirits, but if you really want your child’s fever to break, get off your high horse and find someone who knows the ritual. It’s hard to believe that it really always worked; it probably didn’t. But since it was not used routinely, there was no averaging of results. Anything that we turn to in an extremity usually seems more effective.
The prevailing charms we read about were to induce love or pregnancy, or to inflict death on an enemy. For saving life in times of sickness, or for carrying a baby to term, occult magic’s boundary with natural magic—that is, early science—was shaky. For inflicting death for revenge, or to steal a man’s affection from another woman, the boundary was quite clear. This type of magic was a sin, even in the eyes of those who sought it. We read of some using wax images of their victims, which of course was right in line with natural magic’s principle of “like affects like,” but in an aggressive way. Similarly, a knife stuck into the wooden wall of a dairy barn could resemble the cow’s teat and therefore steal milk by magic.
Another type of medieval magic was the practice of divination: using objects and events to tell the future. Of course, this practice went way back into antiquity. Specialists in divination used to tell the future by seeing omens in flocks of birds, or in the entrails oozing out of a dead animal. Medieval diviners listened to thunder and bird calls. There were also significant patterns in oil or water, especially when it was holy and placed on someone’s fingernail. We have some vestiges of medieval divination that survive in customs of divining whether an unborn baby is male or female. Have you heard that your wedding ring, suspended on a red thread, will swing one or another direction based on the baby’s sex? Astrology was also part of divination, since the thunder meant something different on an “Egyptian Day” of bad luck or under certain signs. This was probably high-class divination for the rich, since it involved some learning.
The worst kind of magic was necromancy, and here we have another root of modern fantasy about magic. Necromancy was the fancy-pants college boy among other magic branches; it was not your old herb-woman’s charm or the wandering divination quack’s pronouncements for a penny. Necromancy was theology, turned inside out. It required Latin and books. It was made up of rituals and prayers done in a very wrong way.
Basically, there were two career paths for failed university students: stand-up comic and necromancer. All that education could lend itself to some thigh-slapping mimicry and satire, and castles were paying for that. But it could also bring in much higher fees if it were turned to support the desires of wealthy broken hearts or vengeful siblings. Necromancers did all the stuff we see in vampire movies: they had hoary old books, they drew circles and lit candles, they recited prayers backwards. They were more likely to have read the esoteric alchemists, too, so they might peddle “secrets” that could make the magic more powerful. They could use demons’ names or even invert the exorcism rites to call, not expel, demons. Some of this material came from orthodox Christian books and manuals that were available in any cathedral town, and could be invented by any priest who wanted to slip off the path of truth. Other material was specialized and not well known.
The official hierarchy was against occult magic. We have a decree of Charlemagne that anyone found practicing sorcery would become a slave on an estate owned by the church. Much of what we know about daily practice of occult magic comes from the church’s manuals for priests that listed sins with suggested penances. We also have records of the Inquisition among the Cathars in southern France. This Inquisition was more of a forensic investigation and mass-scale interview program than a witch-burning spree. They asked the peasants if they knew anyone who practiced magic, then investigated these reports. The church itself did not condemn witches to death, but imposed penance on them. Local barons and kings, however, often took it a step farther.
Before the 14th century, there were not many trials of witches. Most of the records we have (outside of the Cathar region) are about high-profile cases. One Frankish king died suddenly, while another remained childless, and people suspected the malign hand of dark magic in both cases. The Templar Knights were accused of witchcraft, and that was one of the chief charges used to condemn its last leaders to death in 1314.
This all changed after the Black Death years. When half the population is suddenly dead, the surviving half becomes very interested in life after death, contacting the dead, and influencing life and death. Immediately after the plague ended, most areas experienced a time of great sexual freedom. It seemed like the old order was dead, and they also needed to repopulate! In this context, there was a great demand for charms to use against the fathers of babies who had absconded or chosen a different baby-mother. That’s one way that the female form of the “witch” became prevalent. Men were the victims, women were controlling them. In one charming anecdote, a witch supposedly charmed away men’s penises if they abandoned the girl, and then she kept them in a box. They were still alive and could be returned for a fee, or for repentance. (What did the witch feed them? Guess.)
The old medieval view had been that spiritual things were for others, especially for the monasteries. The priests and monks prayed, while the rest of us farmed. But after the plague years, and during repeat visitations of the plague, the lay people wanted to participate in spiritual things. Orders of Friars preached to the common people, and educated people began owning and reading the Bible in Latin or Greek. On the other side, the intense interest in spirits and the dead was also turned in the occult direction. Everything about magic became more developed and common. In 1431, the English accusation that Joan of Arc was a ‘witch,” with her public burning, made witchcraft even more famous, but that’s near the end of the medieval period. Most of the witch-hunts we think of as medieval were actually from the Renaissance-Reformation period, when chronic war and charges of heresy made executions seem appropriate. The peak of witchcraft trials, at Salem, were in the 1690s, 250 years after the official close of the Middle Ages.