Overview
In Christian theology, baptism of blood or baptism by blood, also called martyred baptism, is a doctrine which holds that a Christian is able to attain through martyrdom the grace of justification normally attained through baptism by water, without needing to receive baptism by water.
Patristic period
Cyprian of Carthage in a letter of 256 regarding the question of whether a catechumen seized and killed due to his belief in Jesus Christ "would lose the hope of salvation and the reward of confession, because he had not previously been born again of water", answers that "they certainly are not deprived of the sacrament of baptism who are baptized with the most glorious and greatest baptism of blood".
Cyril of Jerusalem states in his Catechetical Lectures delivered in Lent of 348 that "if any man receive not Baptism, he hath not salvation; except only Martyrs, who even without the water receive the kingdom".
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