Letter: Star of Bethlehem

Sir: Johann Kepler observed on 17 December 1603 a striking conjunction of Saturn and Jupiter in the constellation of Pisces and calculated that a similar conjunction must have occurred in 7BC (Saturday Essay, 19 December).

He speculated that this might have been the true year of Jesus' birth, it generally being agreed that the original dating of the nativity to the year designated 1AD by the 6th century abbot Dionysius Exiguus derived from a miscalculation. Kepler found support for his theory in a Jewish rabbinical reference to a Messiah (Christos) appearing, when Saturn and Jupiter would be in conjunction in the constellation of Pisces.

Jesus was born during the reign of Herod the Great . As Herod died in 4 BC, Jesus would have been born before that. "Then Herod ...slew all the children ... from two years old and under, according to the time which he had diligently inquired of the wise men ... " (Matthew 2:16). Therefore the birth would have been at least two years earlier, say 7-6 BC.

The Magi, being fully aware of the consequences of a rival to the Herod dynasty, deliberately deceived Herod, not only about the place where Jesus was born, but also about the date. The Magians referred to a Samaritan calender which made 7BC the birth year of the Christ, but Herod understood this to be 5 BC. So he waited for two years and when he discovered his mistake looked for children who were two years old.

A celestial phenomenon coinciding with the birth of a king would be too good an opportunity for Matthew to miss out of his Gospel.

December 25 is the birthday of Mithras (Sol Invictus), god of the Roman religion jockeying for position with Christianity before the 1st Council of Nicaea. This was convened in 325 by the Emperor Constantine, ostensibly to solve the problem created in the Eastern Church by the "heresy" of Arius of Alexandria, which held that Jesus the Christ was not divine but a created being.

First and foremost, however, Constantine needed the council to create a pre-eminent position of his imperial self. He needed his imperium to resemble the order of heaven, with himself echoing the role of Sol Invictus at the top.

By forcing the attending bishops to formulate a belief structure to which "everybody" would agree (or else!), the council tacitly validated the emperor's earthly rule, in return for the imperial acceptance of the bishops and their faith.

December 25 was a convenient date to transfer worship from Mithras to the Christ without fuss.

P R HEMS

Cockfosters, Hertfordshire