Welcoming the Shechinah
Kiddush Levana or Blessing of the Moon (Birkat HaLevana) is seemingly small rabbinical mitzvah based on Talmud Sanhedrin:
Rabbi Yohanan is quoted in the Gemara Sanhedrin 42a saying: “One who makes the blessing for the new moon in its proper time is considered as if he welcomed the Shechinah”
Gemara is drawing a parallel between the physical moon on one side and Shechinah/Jewish people on the other.
Just like the physical moon is constantly going through the cycle of visible waxing and waning, so does Klal Isroel/Shechina is always going through ups and downs, reflecting the G-d’s light more or less, channeling more Godliness into the world or less.
Deeper meaning of Kiddush Levana.
Here is more accurate translation of the this verse from Gemara Sanhedrin. It helps us to grasp a deeper meaning of the mitzvah Kiddush Levana:
“One who makes the blessing for the new moon in its proper time is considered as if he received/accepted the Shechinah”.
So rather than ambiguous “greeting”, Kiddush Levana helps us to accept/connect to the Shechinah!
When we do the Kiddush Levana at the right time, being in the state of love and joy, we connect with the Shechinah to give it strength. Our focus on the mitzvah allows Shechinah to affect our day-to-day life, filling in our material and spiritual lack. In other words, we benefit from boosted Hashgacha Pratit – individual Divine Providence in our life.
So “receiving” Shechinah as a consequence of Kiddush Levana is quite literal – one receives Shechinah into his life for the month to follow.
The “greeting” translation is quite accurate as well. The “greeting” implies exchange of energy, exactly what is happening during Kiddush Levana.
Timing of the mitzvah.
We can glean additional meaning of the mitzvah if we look closer into WHEN we do Kiddush Levana. According to Halachah, we do it from the 7-th day to the 14.75 days of the lunar cycle. This means we only “connect” while the moon had reached certain maturity but is still growing .
This timing allows us to “hitch the hike” of the growth/expansion energy radiated by the moon/Shechinah.
It also explains why, according to Halacha, one cannot make Kiddush Levana after the moon starts waning. We want to hitch a hike on the Chesed/Expansion momentum of the first half of lunar month. After the 14.75 days of the moon cycle, however, the Moon radiates Gevurah/Contraction energy. Some smartphone weather apps show moon phases as well as exact time of the cycle, for example “weather & clock widget” for Android. If making your Kiddush Levana on 15-th, you should check that 14 days and 18 hours has not yet passed.
So this brief prayer service becomes very important factor when we align our life with the moadim and zmanim. Kiddush Levanah helps us to ride the “life” wave, not crash into it.
See also the related topic on Rosh Chodesh.
Halachic details along with recommended Kavanot (intentions) – “Ben Ish Chai” on the Kiddush Levana:
Good in-depth article on Kiddush Levana addressing other aspects of the mitzvah.