Why it was celebrated on December 25th is another question. No date for the birth of Jesus can be found in the New Testament, which is concerned more with the question "Who is Jesus?" than the date of his birth. Early Christian speculation about his birth date was influenced by the symbolism of the changing seasons, then popular in religious thought, which paid careful attention to the equinoxes and solstices of the sun. Christian scholars speculated that Jesus was conceived at the spring equinox (March 25th) and therefore was born on December 25th, the date of the winter solstice.