This month shall be unto you the first of the months (Exodus 12:2).
The Jewish calendar has two New Years. Rosh Hashanah, the first day of Tishrei, which marks the beginning of the calendar year, is a day of judgment, signifying that we are held accountable for our behavior. The first day of Nissan marks the beginning of the month of our liberation from Egypt, an event which teaches us that God watches us, that He cares about us, and that even distressful experiences, such as the bitter enslavement in Egypt, are part of a Divine master plan.
Six months separate the two New Years. The personal inventory and the analysis of our mistakes and character defects which we do during the solemn days of Tishrei are very sobering tasks. On the other hand, realizing that we hold a lofty status as children of God and that we are constantly under His vigilance, which is emphasized in Nissan, is exhilarating and elating. Both attitudes are indeed essential, but if one tries to achieve them simultaneously, one may end up in a state of confusion.
In the third chapter of Ecclesiastes, Solomon points out that we should dedicate appropriate times in life for conflicting acts and attitudes. He says, "There's a time to plant and a time to uproot" (3:2), and "There is a time to cry and a time to laugh" (3:4), etc. A healthy adjustment to life is a delicate balancing act. With proper learning and guidance, we can learn to determine appropriate times for what we are supposed to do.