Salome was a daughter of Joseph the Betrothed, who had four sons and three daughters by a previous marriage: James, Joses, Jude, Simon, Esther, Martha, and Salome. Thus, our Savior, according to the flesh, was an uncle of St. John the Theologian. John was a fisherman by trade. He and his brother, James, were laboring with their father, Zebedee, when Jesus called them to be disciples. Later, James and John became known as "The Sons of Thunder."
John was in the circle of “the Three,” along with Peter and James. He was present at the miracle of the raising of the daughter of Jairus. He was also present on Mount Tabor at the Transfiguration of Christ.
At the Mystical Supper, the Lord allowed him to recline on His breast. When the Jews arrested the Lord, John followed Him to the house of the high priest. John was the only male disciple to stay at the Cross with the Theotokos and the other women. Jesus committed His mother to the care of St. John, and from that day the Beloved Disciple took her into his own home. Interestingly, he would spend much of the remaining time of his life in the presence of a holy person -- the Mother of God.
He was the first male disciple at the tomb following the resurrection. He saw the resurrected Christ, received the Holy Spirit, and a commission to preach the Gospel. He was present on the Mount of Olives at the Ascension of the Lord. He was also in the Upper Room on the Day of Pentecost when the Holy Spirit descended in the form of fiery tongues. Later, when the Apostles drew lots to learn where each should go, it fell to St. John to preach the Gospel in Asia Minor. He was about 56 years old when he departed from Jerusalem.
He made his way to Ephesus where he remained for about 9 years strengthening the church and preaching the Gospel. The Emperor Domitian banished John to the island of Patmos where he wrote his Gospel. Heavenly visions were common to him. He wrote the Book of Revelation there as well. John spent a total of 15 years in exile on Patmos.
St. John was freed from exile during the reign of the Emperor Trajan who allowed the Apostle to return to Ephesus. There he labored for Christ another 26 years. He wrote three Epistles while in Ephesus. He also installed Timothy as the first bishop of the city. St. John reposed in peace at the end of the first century.
Also, St. John the Theologian is the patron saint of those suffering from heart conditions.