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It is not clear where the idea that the relatives of someone who was crucified would pay for their legs to be broken as an act of mercy comes from. Crucifixion was a form of execution that was used in ancient Rome and other cultures for punishment and as a deterrent. It involved affixing the condemned person to a wooden cross or stake using nails or ropes and leaving them to die. There is no historical record of the relatives of crucified individuals paying for their legs to be broken as a mercy.

Leg breaking was not a standard practice in the execution of crucified individuals. However, it is possible that in some cases, the executioners may have broken the legs of those who were being crucified in order to hasten their deaths. This was done by striking the legs with a blunt object, such as a club, which would cause the person to suffocate more quickly. This practice is mentioned in the New Testament of the Bible, in the account of the Crucifixion of Jesus.

It is important to note that crucified individuals would often suffer a great deal of pain and suffering before they died. The process of being crucified could take several days, and those who were crucified were often left exposed to the elements and vulnerable to attack by animals and insects. It was a brutal and inhumane form of punishment, and there is no evidence to suggest that the relatives of those who were crucified would pay for their legs to be broken as an act of mercy.