Last week in Parshas haChodesh we read that Bnei Yisrael on Rosh Chodesh Nissan were given the instructions to take the korban Pesach. Shemos 12 ends “vayeilchu va’ya’asu Bnei Yisrael”, which implies immediate action in response to the command, which was impossible – the command was given on Rosh Chodesh, but the taking of the korban was not until the 10th of the month. I spoke about this at the bar mitzvah last week. Rashi quotes the Mechilta that once one makes a kabbalah to perform a mitzvah it is as if the deed were done already. The effect of such a kabbalah is powerfully illustrated in the story (B.M. 84) of Reish Lakish, who was a famous robber before becoming the great student of R’ Yochanan. The gemara describes how he leapt across a river to attack R’ Yochanan, but R’ Yochana was able to turn him to tshuvah. Once Reish Lakish agreed to join the yeshiva, he found he could not leap back across the river he had just crossed. The kabbalah of Torah and mitzvos literally transformed him on the spot. This kabalah and the transformation it produces is what the celebration of bar mitzvah is all about.
The question remains, however, why the command to take the Korban Pesach was given on Rosh Chodesh when it could have just as easily been given on the 10th of the month. What purpose did these 10 days serve? “Mishcha u’kchu” meant Bnei Yisrael first had to separate themselves from the idolatry of Egyptian culture, and only then could they properly offer the korban pesach. Even though we are aware of the Talmudic dispute whether the world was created in Tishrei or Nissan, we usually think of these time periods as sharing a common theme. However, if Rosh Chodesh Nissan is really a Rosh haShana, we can appreciate the Shem m’Shmuels’ chiddush that these 10 days between Rosh Chodesh and 10 Nissan correspond to the aseres y’mei tshuvah which culminate in the kabbalas pnei Hashem (like we find on Yom Kippur) in the korban Pesach and the leil haSeder.