The Feast of Tabernacles Theory
Jesus was thirty when he began a ministry that lasted three and a half years. This would put the start of his ministry during the fall at the Feast of Tabernacles and end three and half years later during the feast of Passover. The Feast of Tabernacles occurs in September/October. Proponents of this theory argue that angels appeared to shepherds and that sheep were put up during the cold winter months. The Feast of Tabernacles is also called the Feast of the Nations or Feast of the Gentiles. The angels brought the shepherds "tidings of great joy to all nations." The Hebrew word for Tabernacle, sukkot, can also be translated as "manager."
However, the Feast of Tabernacles was a pilgrimage feast. Jewish people were required to travel to the Temple in Jerusalem in order to celebrate the feast. Jesus was born 50 miles away in Bethlehem.The reason for the pilgrimage to Bethlehem is that Caesar Augustus ordered everyone to register for a tax in their hometown. Throngs of Jewish people would have arrived in Jerusalem for the Feast of Tabernacles. It would have been easier for the Romans to obtain tax information when the Jews entered the city for the feast.