This week's section features the first mitzvah of the Torah: the sanctification of the months. Although other precepts have appeared since the beginning of the text, only now does God "officially" instruct Moses to tell the Jewish people the details of something they must do for all future generations.
The precept itself consists of determining the birth of the new moon each month and declaring the beginning of the new month. This is significant for determining holidays like Passover, where there is a strict prohibition against eating chametz (leavened bread), and therefore it is necessary to know the exact day the month begins and, consequently, the start of the holiday. Today, this mitzvah cannot be fulfilled because we do not have a court appointed in the Land of Israel with a tradition of appointment dating back to Moses that can effectively declare the beginning of a new month. Today, the entire Jewish people operate according to a pre-calculated calendar.
In fact, this is where the custom of calling the Shabbat before the beginning of a month "Shabbat Mevarjim" comes from, that is, a Shabbat that blesses the new month, and of declaring, after the Torah reading, that the new month will be called such and such and will begin on such and such a day, so that people know in advance and we remember the original ceremony of sanctifying the new month.
Even if we cannot fulfill the mitzvah in practice, we can still draw useful lessons from it for contemporary life. This precept is related to the idea of the sanctification of time. In its original form, it concerned the sanctification of the first day of the new month to bring the specific offerings for that day to the Temple. If the day was not holy, it was not appropriate to perform the rituals of a holy day.
Today, this precept teaches us to sanctify time. God gives us a life with a specific amount of time, enough to accomplish all that is expected of us, both personally—that is, in our personal growth and development—and collectively—our influence on the environment in which we live. However, we must not only use time to the fullest, that is, take advantage of every moment for the various necessary tasks, but also, since time is, so to speak, empty, we must infuse it with holiness.
A practical way to express this idea is to turn off your cell phone for five minutes and dedicate that entire time to Torah study. Even if it's just reading a couple of psalms, when you dedicate time to something holy, you sanctify that time.