Menachot 68 - Remembering the Temple

We learned that Rabbi Yehudah does not establish a preventive decree to stop people from eating new grain before its time, but the Sages do. However, we saw them having the opposite views! For example, if one missed searching for leaven before Passover, Rabbi Yehudah prohibits him to search, lest he comes to eat it. The answer is that Rabbi Yehudah is not worried about new grain, because people do not eat it all year, but they do eat leaven. And the Sages? They say, he is searching for leaven to burn it, will he eat it?

If there is no Temple and no Omer offering, the new grain becomes permitted with the sunrise on the second day of Passover. However, Rabban Yochanan ben Zakkai established that the new grain should not be eaten until the end of the day. Why? Any time the Temple may be rebuilt. Then the people may make a mistake and reason thus: last year we ate the new grain right after the first day of Passover, so let's do it this year! And they won't know that last year there was no Omer, but now that there is one, they have to wait.

Art: Charles Henry Passey - Sheaves Of Wheat After The Harvest