One of the twelve apostles in Mark 3: 18 and Matt. 10: 3 but there are variations in the names of the twelve in each of the four lists in the NT. In Luke 6: 16 and Acts 1: 13 ‘Thaddaeus’ is replaced by ‘Judas’, son of James. He is also sometimes known as Lebbaeus (Matt. 10: 3, NRSV marg.) Such variations are due to the traditions being transmitted through and by different Christian communities.