The day before each Rosh Chodesh (beginning of the month) is referred to as 'Yom Kippur Katan," the "Little Yom Kippur." R' Gedalya Schorr, in explaining why this is the case, first discusses the purpose of Yom Kippur. Yom Kippur, simply stated, is a day for one to take an accounting of what he or she has accomplished or failed to do. It is time for people to inspire themselves, to arouse within their heart and soul a desire to accomplish more, to strive for greatness.

There are two approaches that can be taken when it comes to self-motivation. One approach is to focus on that which we are lacking. "Why can't I control my anger, why can't I control my evil inclination, etc.?" By accenting our faults, we realize how far we have fallen, and how great the need is to get back on the right track. Another approach is to focus on our aspirations and goals. Our Sages wrote that everyone is required to ask themselves "When will my deeds reach the (level of the) deeds of my forefathers?" A person must realize that he has it within himself to achieve greatness, and that greatness is indeed within reach.

However, regardless of the approach taken, there is another important step. The Kotzker Rebbe said that the distance between heaven and earth is a journey of hundreds of years, but the distance between the mind and the heart is even greater. A person may intellectually acknowledge that there is a task to be done. Yet, if the person does not feel the commitment to that task in his heart, and does not involve his emotions somehow in that commitment, the task will not get done. A person may very well understand that their actions leave something to be desired. Does that person care that this is the situation? A person may have had hundreds of people tell her how smart and capable she is? Does she really believe it? If a person is lacking any feeling and is indifferent about their behavior, the behavior won't change. If a person does not really believe they have the capacity to rise to greatness, they will most definitely not rise to greatness. The gap between the mind and the heart, the intellect and the emotion, must be bridged in order for any goal of improvement to be met.

The moon does not give off any light of its own. It reflects light from the sun. The amount of light reflected varies during the course of a month. At the middle of the month, the moon is in its fullest splendor. At the beginning and end of the month, the moon is but a tiny sliver. As mentioned above, the heart, one's emotions, is compelled to act based on the processes of the mind, one's intellect. The effect the intellect has on the heart varies. At times, an intellectual realization can be so powerful that it results in immediate action. The emotional reaction can be overwhelming. At other times, the power the intellect wields over the heart is minimal. Almost no inspiration results, and a person will maintain the status quo.

The very end of a month, when the moon is barely visible, is an appropriate time to remind ourselves of what we are to be doing with our lives. We can gaze upwards and see almost none of the moon, knowing that a mere two weeks later, the moon will be full. Similarly, we can gaze within ourselves and see not even a tiny spark of inspiration or desire to strive for greatness. At the same time, we should know that we have the ability within us to shine brightly. Right before we begin a new month, we should inspire ourselves to improve, regardless of the method we employ to do. For this reason, specifically the day before Rosh Chodesh is set aside for a day of self improvement and introspection, thus earning it the name Yom Kippur Katan.