Once a month, under an open sky, Jews say a blessing over the moon. The Talmud gives the reason in a sentence attributed to Rabbi Yochanan in the name of Rabbi Shimon bar Yochai: whoever blesses the new moon at its proper time is considered to have greeted the Shechinah, the Divine Presence (Sanhedrin 42a). The ceremony is called Kiddush Levanah, the sanctification of the moon.

The blessing

The blessing praises Hashem “who with His word created the heavens, and with the breath of His mouth all their hosts.” It goes on to say that He gave the heavenly bodies a law and a set time, so that they would not change their task. The closing lines describe the moon as “a crown of beauty for those carried from the womb, who will one day be renewed as it is.” In the tradition the moon’s cycle is a picture of the Jewish people, who shrink in exile and are expected to grow full again.

It is said standing, outdoors, with the moon in view, and ideally after Shabbat ends, when a person is still dressed well (Shulchan Aruch, Orach Chayim 426). Communities differ on how many days after the new moon to begin, and on when to stop, around the middle of the month. The blessing is followed by the greeting Shalom aleichem, said to the people nearby.

The moon in Kabbalah

The Kabbalists identify the moon with Malkhut (Kingship), the tenth of the sefirot (Divine attributes), which carries the Shechinah and has no light of its own. It receives from the sun, just as the Shechinah receives from the sefirot above it. The waning and renewal of the moon follow the same pattern as the exile of the Shechinah, which is covered in The Shechinah in Exile. The monthly cycle is also the subject of Rosh Chodesh and the New Moon.

When the blessing is said on Saturday night, it follows Havdalah, so the week’s first act is a blessing over something that will grow.