The time period of the Middle Ages was predominated formed through a Christian way of life, concentrating on a life after death. Those people who tried to lead a flawless life were looked upon as saints. Since they were thought to be middlemen between God and the rest of humanity, their veneration already began in the ancient world. In the early stages of Christianity, martyrs were honoured as being saintly, for they had willingly died because of their faith. In the 4th century the number of martyrs decreased and in their place bishops, monks and hermits were venerated. They were thought of being martyrs in a supernatural sense, as they completed a daily martyrdom by mortifying their bodies through their own willpower. The writings about the lives and sufferings of martyrs and saints results in hagiography, which has a special look at the lives and the works of saints. There are several sorts of texts, the vitae, reports of translations, of miracles and the register of saints.As some of the most important examples for the vitae, this work analyses the life and work of Martin of Tours in Vita Sancti Martini, written by Sulpicius Severus in the year 396, and of Severinus of Noricum in Vita Sancti Severini, which was drawn up by Eugippius between 509 and 511. Initially, they are analysed to examine their differences and similarities. Though they are similar, it is shown in the vitae that hagiography does offer variable patterns. This part in my work is followed by an intensive discussion of the image of Martin and Severinus in the vitae, where the protagonists are portrayed from a catholic point of view. Resemblances in the description and the behaviour of both are characterized by their personalities and actions. I also show that the vitae play an important role as historical and political source in the historical Church. A comparison of these two vitae shows a common basic structure of hagiographic writings, but also clearly points out their differences.