The week before Rosh Chodesh Nissan, we read the last of the four special parshahs, Parshas Hachodesh. In it is discussed the first mitzvah given to the B’nei Yisrael as a nation, the mitzvah of Rosh Chodesh, Sanctifying the New Moon. This mitzvah is followed in the parshah by the mitzvah of Korban Pesach (Passover lamb offering) and other laws of Pesach.
It makes sense logically that Hashem would give the mitzvah of Rosh Chodesh together with the laws of Pesach since sanctifying the moon would determine what day the holidays would begin. When Bais Din (Jewish Court) would determine based on the testimony of two witnesses that it was Rosh Chodesh, they would declare that day the first of the month and start counting the days of the month from there, therefore determining the starting day for Pesach and the other holidays. However, perhaps we can find a deeper connection between the mitzvah of Rosh Chodesh and Korban Pesach.
Chazal tell us that in ancient times, the god of Egypt was the sheep. It is for this reason Yosef tells his brothers in Parshas Vayigash that the Egyptians hated all shepherds, for someone to lead their god and not have the god lead itself was the highest form of degradation. Furthermore, the constellation for the month of Nissan, the current month during our Parshah’s events, is Aries, the lamb. Hashem specifically commanded the Jewish People to slaughter a lamb as the Pesach offering in order to show that he was ruler of all the land including up in the sky by the constellations and down on the ground with the sheep. Additionally, Aries is the “first-born” of the constellations as it comes first in line, Hashem wanted to destroy not only the first-born of the Egyptians down on the ground but also the first-born of the sky.
Hashem commanded the Jews to designate the lamb that they were going to use for the Korban Pesach on the Tenth of Nissan, five days before they actually sacrificed it. One of the reasons Hashem had them separate it so early was to show that even early in the month, when the constellation is still “powerful”, Hashem is still more powerful than it.
It is for these reasons, says the Kli Yakar, that Hashem gave us the mitzvah of Rosh Chodesh right before the mitzvah of Korban Pesach. By knowing the exact date and how far into the Month of the Lamb we were, Hashem’s authority was shown that much more to everyone. So when we read Parshas Hachodesh this week and say Hallel on Rosh Chodesh next week (and in a few weeks when we celebrate Pesach), realize that this is not any old parshah and this month is not any old month, when we celebrate the sanctification of this month, we are celebrating the complete rule and authority Hashem has over the world. May we merit that this month, this realization will be spread throughout the entire world with the coming of mashiach. And may the pasuk “ביום ההוא יהיה ה אחד ושמו אחד” “On that day, Hashem will be one and his name will be one”, be fulfilled.