Just as a coin has two sides, both valid, so too does the personality of St. John the Apostle, author of the fourth Gospel, the three epistles, and the Revelation. St. John's guiding theme was that of love, but he also had the strength and willpower to be named "son of thunder." "The beloved one," as John was often called, is evident of his intimate relationship with Jesus. John also speaks of love throughout his writings, especially 1 John 4:8—"...for God is love." John, along with his brother James, received their name, "sons of thunder," in Mark 3:17.