Without wasting time, Saint Martin began his apostolic ministry. One of the tasks he set for himself was to achieve the conversion of King Charraric (Carriaric), a Suebian king who had adopted Arianism. The king had a son sick with leprosy and, wanting to win God’s favor, he sent a group of representatives to the tomb of Saint Martin of Tours, to ask for the health of his heir.
The first mission did not achieve the long-awaited miracle, and the king decided to send a new delegation, this time, with an offering in gold and silver of the same weight as his son; Furthermore, he promised to reject the heresy if the saint of Tours granted him the miracle. Then the young man miraculously recovered his health, so the monarch kept his word, which led to the conversion of the entire Swabian people to sound doctrine.
In the middle of this process of spiritual purification was Martin, who had become a faithful friend and advisor to the king. Charrarico would not have opened his heart to the truth without the testimony, teaching and prayer of this saint. In this way, Martin was also able to open the soul of the Suebi to the truth of the Gospel.
The archbishop of Braga, Lucretius, would create a diocese in Dumio, of which Martin would be its first bishop (556).