וּשְׂעִיר עִזִּים אֶחָד לְחַטָּאת לַיהֹוָה
And one young male goat for a sin offering to the Lord.
The Talmud (Chullin 60b, quoted by Rashi on this verse) indicates that at the dawn of creation the sun and moon were of equal size, until the moon approached God and complained that two kings cannot wear one crown. In response, God shrunk the moon. Enigmatically, according to the Talmud, the goat sacrifice that we offer on Rosh Chodesh is an atonement of sorts for God Himself for making the moon smaller. God’s diminution of the moon (pegimas halevanah) is symbolic of the fact that He left creation incomplete. Homiletically interpreting the words לְחַטָּאת לַיהֹוָה as “a sin offering for God,” the Talmud states that the Jewish people bring a sacrifice to atone, as it were, for the Holy One Blessed be He for not having completed the work of creation.
This imperfection is reflected in man’s constant struggle with nature and its catastrophes. Nature’s hostility to man is represented by pegimas halevanah. God wants man to rule and be victorious over nature; to do so, man himself must symbolically reverse pegimas halevanah, and thus become a partner with God in creation. Man is obliged to perfect what his Creator “impaired.” Pegimas halevanah also represents the exile of the Divine Presence, reflected in Israel’s own exile and the resultant persecutions. Physical reality and spiritual-historical existence—both have suffered greatly on account of the dominion of the abyss, of chaos, and their fates parallel one another. As a result of the difficulties that He has caused man through both natural catastrophes and persecution, represented by pegimas halevanah, God requires an “atonement” on Rosh Chodesh. (Boston, 1967; Halakhic Man, pp. 106-107)