St. Augustine of Hippo (354-430 CE) and many medieval theologians after him, including philosopher and theologian Thomas Aquinas (12245-1274) believed demons were the only real agents capable of activating magic. People believed that demonic entities executed the prayers or invocations for harm or punishment inscribed on curse tablets. Consequently, the tablets were placed in the sanctuaries of underworld divinities (Collins).
It was necessary to recite the text while engraving it on the metal. With a buried binding spell, the tablet is hidden in the earth or sea, river, water pipe, well, or tomb. The spell caster sought contact with the underworld of the dead, in order to get these words to reach the deceased. The dead man in his tomb became a kind of “infernal postman” who took the text to the divine or demonic addressee. People who had died at a young age or violently were considered ideal helpers of sorcerers, because they nurtured a grudge against the living (Graft).
In ancient Greece, during the fourth century BC, there was a booming trade in magic. A popular form was the curse etched into a lead tablet, which was then folded and pierced with a nail. Such curses seem to have been used against rival businessmen and athletes, to win the affection of a potential lover or to ensure success in legal proceedings (Dell)
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Collins, Derek Magic in the Ancient Greek World, Wiley-Blackwell, 2008.
Dell, Christopher The Occult, Witchcraft and Magic: An Illustrated History, Thames & Hudson, 2016.
Graf, Fritz Magic in the Ancient World (Revealing Antiquity, No. 10), Harvard University Press, 1999.