“My walk on the moon lasted three days. My walk with G-d will last forever.” (Charles Duke – Lunar Module Pilot, Apollo 16)
Kiddush Levanah finishes with Aleinu Leshabeyach, which is the concluding Tefillah for most of our daily Tefillot. Why was it added to Kiddush Levanah? The Mishna Berurah is the Chofetz Chaim’s masterful commentary on Orach Chaim, the first section of the Shulchan Aruch. It defines the rules of prayer and the synagogue, Shabbat and the Yamim Tovim. Aside from his main commentary, the Chofetz Chaim also authored the Biur Halacha, which is printed on the same page, together with the Mishna Berurah. The Biur Halacha is an analysis of the many approaches that are found within Jewish law and custom.
In the Bi’ur Halacha (426), the Chofetz Chaim explains that the Ashkenazic custom to recite Aleinu Leshabeyach at the end of Kiddush Levanah derives from a concern that people might otherwise mistakenly assume that we are praying to the moon. In order to prevent this serious mistake, the practice of saying Aleinu Leshabeyach was instituted because Aleinu Leshabeyach clearly states that all of our praises are directed only to Hashem.
For this reason, the Mishna Berurah rules (ibid.) that we should not stare at the moon while reciting Kiddush Levanah. Rather, we should glance at the moon briefly just before saying the blessing, and we should not look at the moon again until after completing Kiddush Levanah.
Minhag Yisrael Torah, an anthology of Jewish customs, adds another intriguing reason for reciting Aleinu Leshabeyach at the conclusion of Kiddush Levanah. He cites the unknown author of the foundational Halachic compendium, Kol Bo, saying that according to ancient tradition, Aleinu Leshabeyach was composed by Yehoshua. But what is the connection between Yehoshua and Kiddush Levanah?
