Most people assume Jesus was born on Dec. 25. After all, that's the
date celebrated throughout the world as the day of His birth. A careful
analysis of Scripture, however, clearly indicates that Dec. 25 is an
unlikely date for Christ's birth. Here are two primary reasons:
First, we know that shepherds were in the fields watching their flocks
at night at the time of Jesus' birth (Luke 2:7-8). However, shepherds
did not remain in the fields of Judea at night during December due to
lack of forage and the bad weather.
According to Celebrations: The Complete Book of American Holidays,
Luke's account "suggests that Jesus may have been born in summer or
early fall. Since December is cold and rainy in Judea, it is likely
the shepherds would have sought shelter for their flocks at night" (p.
309).
Similarly, The Interpreter's One-Volume Commentary says this
passage argues "against the birth [of Christ] occurring on Dec. 25 since
the weather would not have permitted" shepherds watching over their
flocks in the fields at night.
Second, Jesus' parents came to Bethlehem to register in a Roman census
(Luke 2:1-4). The Romans would have known better than to have taken
such a census in the dead of winter, when temperatures often dropped
below freezing and roads were in poor condition for traveling. Taking
a census under such conditions would have been self-defeating.
So if Jesus Christ was not born on Dec. 25, does the Bible indicate
when He was born? The biblical accounts point to the autumn of the year
(in the northern hemisphere) as the most likely time of Jesus' birth,
based on details of the conception and birth of John the Baptist.