WORD OF THE MONTH

A weekly feature of Torah Tidbits to help clarify practical and conceptual aspects of the Jewish Calendar, thereby better fulfilling the mitzva of HaChodesh HaZeh Lachem... 

Although we mark Rosh Chodesh Adar on both Friday and Shabbat, in the time of the Sanhedrin, there was always only one day of Rosh Chodesh, regardless of whether the waning month had 29 or 30 days. Furthermore, with the Molad of Adar on Friday morning, the moon will not be visible on Friday evening. Meaning that if we had a Sanhedrin today, neither Friday nor Shabbat would be Rosh Chodesh, but rather Sunday would be. (That would make "regular" Purim fall on Shabbat rather than Shushan Purim - something that cannot happen in our fixed calendar. Then everyone else but we Yerushalmis would have Shabbat-Purim. Besides the point.) If Sunday would be Rosh Chodesh, and not Friday-Shabbat, does that mean we are wrong? Does it even mean that we should take our knowledge and declare Sunday Rosh Chodesh? As they say... LO V'LO. No and No. The fact is (according to Rambam) that we have a dual Tradition concerning fixing Rosh Chodesh. Each is RIGHT in its era. Without a Sanhedrin, we have a calculation. Anything else is wrong.

The Four Parshiyot & Beyond
The following chart describes the Shabbatot from Sh'qalim through Pesach for the four possible arrangements of years

In the hard-copy of TT, there is a table. Here, each line will have the four elements of each row, separated by spaces. If you are printing this out and want it to look decent, you'll have to reconstruct the table. If you use a monospacing type font, it should look like a table. Proportional spacing will require a little playing with.