Saint Jude, also called Thaddeus was the Son of Cleophas and Mary (who stood at the foot of the Cross, and who anointed Christ's body after death); brother of Saint James the Lesser; nephew of Mary and Joseph; cousin of Jesus Christ, and reported to look a lot like him is thought to have been a fisherman prior to becoming an apostle.

Ancient writers tell us that he preached the Gospel in Judea, Samaria, Idumaea, Syria, Mesopotamia (modern day Iraq), and Lybia. Legend claims that he visited Beirut and Edessa as well. According to Eusebius, he returned to Jerusalem in the year 62, and assisted at the election of his brother, St. Simeon, as Bishop of Jerusalem.

He is an author of an epistle (letter) to the Churches of the East, particularly the Jewish converts, directed against the heresies of the Simonians, Nicolaites, and Gnostics. This Apostle is said to have suffered martyrdom with St. Simon by being beaten to death with a club, then beheaded post-mortem in Armenia, which was then subject to Persia. The final conversion of the Armenian nation to Christianity did not take place until the third century of our era. Holy relics of St. Jude can be found at Saint Peter's, Rome, at Rheims, and at Toulouse, France.