Based on the Dvar Malchus of Shabbos Parshas Toldos, 5752
Rosh Chodesh Kislev is a Yom Tov for Chabad Chassidim. Twenty nine years ago on Simchas Torah, 5748, the Rebbe Melech Hamoshiach Shlita had a medical problem with his holy heart and as a result remained in his room. The Chassidim didn’t see the Rebbe until the "shining" day of Rosh Chodesh Kislev, five weeks later. The joy and happiness that the Chassidim experienced then was unbelievable. In the year 5752, the Rebbe Melech Hamoshiach Shlita gave a special sicha that explained the significance of Rosh Chodesh Kislev and the very special connection this day has with the revelation of Melech Hamoshiach.
The new moon appears once again on Rosh Chodesh Kislev, something that reminds us about what we say during kidush livana about the Jewish nation, "...In the future they will be renewed like the moon...", during the geula that is about to happen. During the golus, the Jewish nation is tired and restless, but during the geula we will all be renewed and all of our faults will be corrected.
Why are we compared to the renewal of the moon on Rosh Chodesh, when only a fraction of it (the moon) is illuminated and not compared to the moon when it is full and beautiful as it is on the fifteenth, the middle of the month?
The strongest connection
A Jew's nefesh elokis is referred to by five names. They are nefesh, ruach, neshama, chaya and yechida. Each name describes how we connect with Hashem. The level of nefesh becomes revealed when a Jew fulfills mitzvos with his body. When he/she loves Hashem with the heart, the level of ruach becomes revealed. When we learn Hashem's Torah with our minds and intellect, the level of neshama becomes revealed, and so on.
There's another level in the soul that's referred to as etzem hanishama, referring to the living person himself. This is our strongest connection with Hashem. Hashem looks at him and loves him just as he is, even when he takes care of himself, eats, drinks, sleeps, or sleeps. The fact that we live and exist comes from Hashem Himself.
The etzem hanishama has unlimited powers. They are revealed only when a person is confronted with danger. The person at that time all of a sudden displays super human powers and does everything in order to save himself.
When a person becomes extremely happy he also acts differently and can do things that no one ever thought he could do. But generally speaking we don't use our etzem hanishama on a regular basis. Most things that we do have to do with the levels of nefesh or neshama, when we learn Torah and do mitzvos as we always do. When we learn or daven we don't meet up with the etzem hanishama.
The Rebbe Melech Hamoshiach Shlita says that when a person wakes up in the morning, before he says mode ani and before he starts thinking about something, "...His etzem and mihus are awakened..." At the same time Hashem's etzem and mihus are also awakened. Hashem at that moment also becomes revealed.
This only happens in the morning while we are still in bed. A moment later we will have to get out of bed and go daven and learn. Some people will later go to work. We will then forget about the etzem hanishama that we met up with in the morning. The Rebbe Melech Hamoshiach Shlita says that we have to experience and feel the revelation of the etzem hanishama not just as we wake up, but the whole day.
Life centers around Moshiach
The Chazal say that a person should try to bring Moshiach throughout his entire lifetime. The Rebbe Melech Hamoshiach explains, "...The words 'throughout his entire lifetime' imply that every moment of a person's life, whether in the day or during the night, whether awake or asleep, should be used to bring about the yimos hamoshiach. Not only should he use this energy when he's thinking, or speaking, or doing things to bring Moshiach; all of his energy is to be used to bring Moshiach."
The etzem hanishama becomes revealed in the morning. It is the source of life for a Jew. It is the highest level of holiness and is referred to as the level of "Moshiach" within every Jew. In the morning a Jew acquires strength, allowing him to live a life of "Moshiach"...
What does a life of "Moshiach" mean?
A normal person likes to live. A person has energy and desire to do something when concerned with himself. The Rebbe Melech Hamoshiach Shlita demands that we know that our lives are "Moshiach", doing and being so with all of our energy.
Even in the morning after we've already done a thousand and one things, davening, eating, or drinking, everything should center on Moshiach. Then, the etzem hanishama will be revealed the whole day. We don't eat or drink stam. When we eat and drink we think about Moshiach.
The small moon and the big Moshiach
The big illuminating moon symbolizes a Jew that learns Torah and does good deeds. The small moon that is renewed at the beginning of the month symbolizes the Jew that just got up in the morning who still didn't do any good deeds, but, as discussed above, is the greatest time possible. We're looking at an etzem hanishama Jew, Hashem's son.
The moon also refers to Moshiach. The full illuminating moon in the middle of the month refers to Moshiach after he did his job of taking the Jews out of golus and building the beis hamikdash. The small moon that doesn't illuminate and is hardly recognizable at the beginning of the month refers to Moshiach at the beginning of his revelation when we are still in golus, but can recognize and identify the Melech Moshiach. This in essence is the greatest revelation during the yimos hamoshiach, the revelation of Moshiach himself in all of his glory.
Rosh Chodesh Kislev, a time when the moon is renewed once again is an opportune time for the complete revelation of the Melech Hamoshiach.
