The Nativity :Chapter 12-67

On December 25 of 6 B.C. of the old Gregorian calendar of the Astronomy was Saturday, so St. Joseph and Holy Mother Mary could not trip at all. That is why the Jews were not supposed to walk more than 900m on the Sabbath. So I could deny that day automatically.
I named that calendar the old Gregorian calendar of the Astronomy. But those dates of B.C. of the old Gregorian calendar of the Astronomy did not exist in the history of the Jews indeed.