According to the Star of Bethlehem sky charts, Jesus was born in June of 2 BC. The Annunciation had to have occurred at least 9 months prior, which puts it into the previous year. Luke 1:26 says the Annunciation happened “in the sixth month.” This is Elul on the Jewish calendar.
I find it really compelling to put the events of Jesus’ life on to the Jewish and common calendars, because it helps me understand in a more immediate way that Jesus really was conceived and gestated and born in a real place and time to a real woman. He really grew up and taught and died and rose again on real dates, and in a place and time about which we know quite a lot.
It is customary to assume Mary conceived at the Annunciation, but my calculations suggest conception occurred the following month. Luke 1:31 records the angel Gabriel using the future tense – “you will conceive in your womb” – which supports my conclusion.
PLEASE NOTE: On March 31, 2014, I posted a blog about Mary and Medjugorje in which I messed up and said Jesus was born in 1 BC. Sorry ’bout that! I put a note on the blog that it’s wrong. If I get to it, I’m going to redo the Medjugorje calculations and see if they amount to a hill of beans. https://polination.wordpress.com/2014/03/31/mary-has-been-appearing-at-medjugorje-for-33-years/