Mathoni was one of the twelve disciples Jesus chose during his ministry among the Nephites after his resurrection. His name appears in the list of the twelve given in the record, where he is identified alongside his brother Mathonihah, also one of the disciples (3 Nephi 19:4).
As one of the twelve, Mathoni was among those who received power and authority to baptize with water (3 Nephi 12:1). When Jesus asked the disciples what they desired of him, nine of them, Mathoni among those not numbered with the three, asked that their ministry end when they reached the age of man so they might come to him in his kingdom; Jesus promised that after they were seventy-two years old they would come to him and find rest (3 Nephi 28:3).