Rabbi Yudan in the name of Rabbi Tanḥum ben Rabbi Ḥiyya and Rabbi Pinḥas in the name of Rabbi Simon said: After He calls them [both] great, He goes ahead and diminishes them, [saying] “The greater light to rule the day, and the lesser light to rule the night”? (Genesis 1:16). This is bewildering. But it is because one of them entered into the realm of its counterpart.10The moon encroached upon the realm of the sun, as it is visible at times during the day.
For this reason its light was diminished. Rabbi Pinḥas said: Regarding all the [holiday] offerings it says: “One goat as a sin offering” (Numbers 29:5), but regarding the New Moon it is written: “One goat as a sin offering for the Lord” (Numbers 28:15). The Holy One blessed be He said [as it were]: Bring atonement on My behalf for having diminished the moon, as it is I who caused it to enter into the realm of its counterpart.
Now, if this one that entered [into its counterpart’s realm] with permission was diminished by Scripture, one who enters [his neighbor’s realm] without permission, all the more so. Rabbi Levi said in the name of Rabbi Yosei bar Ilai: It is only proper for the greater [older] one to count by the greater thing, and the smaller [younger] one to count by the lesser thing. Esau counts [its years] by the sun, which is the greater, and Jacob counts [its years] by the moon, which is the lesser.
Rav Naḥman said: And this is a good portent. Esau counts by the sun, which is the greater. Just as the sun has dominion during the day and has no dominion at night, so Esau has a share in this world and has no share in the World to Come. Jacob counts by the moon, which is lesser.
Just as the moon has dominion during both night and day, so Jacob has a share in both this world and in the World to Come. Rav Naḥman said: As long as the light of the greater one is in existence, the light of the lesser one is not discernible. When the light of the greater one recedes, the light of the lesser one is discernible. So, too, as long as the light of Esau is in existence, the light of Jacob is not discernible.
When the light of Esau will recede, the light of Jacob will be discernible. That is what is written: “Arise, shine, for your light has come…. For, behold, the darkness will cover the earth, [and thick darkness the peoples, but upon you the Lord will shine and His glory will be seen upon you]” (Isaiah 60:1–2).