The Four Evangelists

Their traditional symbols, the four living creatures, are taken from (anticipated in?)  the prophecy of Ezekiel (1:5-21, 10:20).  Of these same living creatures, borrowed  by the Book of Revelation (4:6-8), St. Irenaeus says, “The lion signifies the royalty of Christ, the calf his priestly office, the man his incarnation, and the eagle the grace of the Holy Spirit.”

Matthew, Apostle and Martyr     

Matthew is called the divine man, since he teaches about the human nature of Christ and since his version of the Gospel begins with Jesus’ paternal genealogy.

Mark, Martyr

Mark is called the winged lion, since he informs us of the royal dignity of Christ and since his version of the Gospel begins: “The voice of one crying in the wilderness,” suggesting the roar of the lion.

Luke, Martyr

Luke is called the winged ox, since he deals with the sacrificial aspects of Christ’s life and since his version of the Gospel begins with a temple scene.

John, Apostle

John is called the rising eagle, since his gaze pierces so far into the mysteries of heaven and since his version of the Gospel begins with a lofty prologue that is a poem of the Word become flesh.

From The Catholic Source Book.

Anno Domini

Before the Christian era years were generally reckoned from the foundation of the city of Rome, or from the election of the emperor.  With the establishment of Christianity they began to be reckoned from the birth of Jesus.  An error in calculation by Dionysius the Younger (who in the 6th century introduced the present method of dating) made the birth of Christ coincide with the Roman year 754, whereas further studies have since ascertained that Jesus was born in 747 or 748, that is 6 or 7 years earlier than Dionysius had supposed.

From this results the curious fact that the Christian calendar which we now use, instead of starting from the birth of Christ, actually started 6 or 7 years after it.  This explains why the date of the birth of Jesus is today reckoned to be 6 or 7 B.C.

As regards the public ministry of Jesus, it is generally held to have lasted little more than 2 years, in view of certain indications in the 4th gospel, which seems the most accurate on this score and speaks of 3 different Passovers.  So, in all probability Jesus began his public ministry towards the beginning of 28 A.D.; his death occurred on the eve of the Passover of 30 A.D.