A Christian martyr
is a person who is killed for following Christianity, through stoning, crucifixion, burning at the stake or other forms of torture and capital punishment. The word "martyr" comes from the Greek word μάρτυς, mártys, which means "witness."
At first, the term applied to Apostles. Once Christians started to undergo persecution, the term came to be applied to those who suffered hardships for their faith. Finally, it was restricted to those who had been killed for their faith. The early Christian period before Constantine I was the "classic" age of martyrdom. A martyr's death was considered a "baptism in blood," cleansing one of sin, similar to the effect of baptism in water. The "baptism in blood" provides an even greater picture, showing the faith that the martyr has for his/her Savior. Early Christians venerated martyrs as powerful intercessors, and their utterances were treasured as inspired specially by the Holy Spirit. The first known Christian martyr was St. Stephen as recorded in the Acts 6:8–8:3
Degrees of martyrdom
Some Roman Catholic writers (such as Thomas Cahill) continue to use a system of degrees of martyrdom that was developed in early Christianity. Some of these degrees bestow the title of martyr on those who sacrifice large elements of their lives alongside those who sacrifice life itself. These degrees were mentioned by Pope Gregory I in Homilia in Evangelia, he wrote of "three modes of martyrdom, designated by the colors, red, blue (or green), and white." A believer was bestowed the title of red martyr due to either torture or violent death by religious persecution. The term "white martyrdom" was used by the Church Father Jerome, "for those such as desert hermits who aspired to the condition of martyrdom through strict asceticism."Blue (or green) martyrdom "involves the denial of desires, as through fasting and penitent labors without necessarily implying a journey or complete withdrawal from life". Also along these lines are the terms "wet martyr" (a person who has shed blood or been executed for the faith) and "dry martyr" which is a person who "had suffered every indignity and cruelty" but not shed blood, nor suffered execution.