A deal with the devil, compact or pact with the devil is a cultural motif, best exemplified by the legend of Faust and the figure of Mephistopheles, but elemental to many Christian folktales. According to traditional Christian belief in witchcraft, the pact is between a person and Satan or a lesser demon. The person offers his or her soul in exchange for diabolical favours. Those favours vary by the tale, but tend to include youth, knowledge, wealth, fame, or power.
It was also believed that some persons made this type of pact just as a sign of recognizing the devil as their master, in exchange for nothing. Nevertheless, the bargain is considered a dangerous one, as the price of the Fiend's service is the wagerer's soul. The tale may have a moralizing end, with eternal damnation for the foolhardy venturer. Conversely, it may have a comic twist, in which a wily peasant outwits the devil, characteristically on a technical point. The person making the pact sometimes tries to outwit the devil, but loses in the end (e.g., man sells his soul for eternal life because he will never die to pay his end of the bargain. Immune to the death penalty, he commits murder, but is sentenced to life in prison).
Great achievements might be credited to a pact with the devil, from the numerous European Devil's Bridges to the violin virtuosity of Niccolò Paganini to the "crossroad" myth associated with Robert Johnson.
The "Bargain with the devil" constitutes motif number M210 and "Man sells soul to devil" motif number M211 in Stith Thompson's Motif-Index of Folk-Literature.
It was usually thought that the person who had made a pact also promised the demon to kill children or consecrate them to the devil at the moment of birth (many midwives were accused of this, due to the number of children who died at birth in the Middle Ages and Renaissance), take part in Sabbaths, have sexual relations with demons, and sometimes engender children from a succubus, or an incubus in the case of women.