Who are St. Simon and St. Jude?
In St. Matthew's Gospel, we read of St. Simon or Simeon who is described as one of Jesus' brethren or kinsmen. His father was Cleophas, St. Joseph's brother, and his mother, according to some writers, was Mary's sister. He would therefore be Jesus' first cousin. St. Simon is mentioned in the Acts of the Apostles as having received the Holy Spirit on Pentecost.
St. Jude, known as Thaddeus, was a brother of St. James the Less, and a relative of Jesus. He was one of the 12 Apostles of Jesus. His attribute is a club. Images of St. Jude often include a flame around his head, which represent his presence at Pentecost, when he accepted the Holy Spirit alongside the other apostles. Another attribute is St. Jude holding an image of Christ.
Biblical scholars agree St. Jude was a son of Clopas and his mother Mary was the Virgin Mary's cousin. Ancient writers tell us that he preached the Gospel in Judea, Samaria, Idumaea, Syria, Mesopotamia, and Libya. 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.
(Please note, Saint Jude is obviously not the same person as Judas Iscariot, who betrayed Jesus and despaired because of his great lack to trust in God's mercy)