Liber Pontificalis
Telesphorus is traditionally considered as being the eighth Roman bishop in succession after Peter. The "Liber Pontificalis" mentions that he had been an anchorite (or hermit) monk prior to assuming office. According to the testimony of Irenæus ("Against Heresies" III.3.3), he suffered a "glorious" martyrdom. Although most early popes are called martyrs by sources such as the "Liber Pontificalis", Telesphorus is the first to whom Irenaeus, writing considerably earlier, gives this title.