Irvin and Sunquist have mentioned in their very well-researched book, History of the World Christian Movementthat “prior to the year 300 AD there had been no consensus among Christians concerning the date on which to celebrate the birth of Jesus Christ. Some argued for a spring date, but others suggested December 25...the day celebrated in honour of the ‘Invincible Sun’. Most Christians came to accept December 25, as the birthday of Jesus, integrating thereby elements of the solar monotheism of Solstice and Roman festival of Saturnalia with Christianity”.
