If eidim came after mincha, then the beis din made it two days RH in Eretz Yisroel. And they would count the next day (i.e) the 31st of the month as day one of Tishrei. But my question is: In reality it WAS Rosh Chodesh on day 30, eventhough the eidim came after mincha - how could the Rabbis push off Rosh Chodesh effectively making Yom Kippur a day later??
Thank you for a response.
Barry Kagan, London, UK
As in all the cases where the Chachamim delayed the occurence of Rosh Chodesh for a reason (such as to prevent Yom Kipur from occurin on Friday), they refrained from saying "Mekudash" even though the Edim came. The Gemara in Rosh Hashanah (Perek 3) makes it clear that the day of Rosh Chodesh depends on Beis Din's sanctification of the day as such, and not on the actual positioning of the moon.
(This concept is reflected in the blessings said on Yom Tov, in which we conclude "Mekadesh Yisrael v'ha'Zemanmim," putting Yisrael first, since the Kedushah of the Yamim Tovim is dependant upon Yisrael (i.e. the Beis Din) sanctifying the day of Rosh Chodesh. In contrast, the blessing on Shabbos which falls on Yom Tov is "Mekadesh ha'Shabbos v'Yisrael v'ha'Zemanim," placing Shabbos first, because Shabbos is not dependant upon Yisrael's sanctification of any day; Shabbos is inherently the seventh day of every week. See Beitzah 17a.)