ישעיהו, פרק ס׳, פסוק כ׳

A prophetic vision of future redemption unfolds, painting a picture of eternal divine light and the absolute end of national sorrow. The primary approach among commentators is that the sun and moon serve as a metaphor for the kingdom of Israel [רד״ק, מצודת דוד, צאינה וראינה]. The promise of a sun that never sets means that the kingdom and its rule will never be destroyed, and its honor will never fade.

Alternatively, this vision describes a miraculous reality where natural light is replaced by the light of God. In this view, the sun represents His eternal light, while the moon represents the prophets and righteous individuals who absorb this divine light and reflect it to others [מלבי״ם]. The constant, unnatural presence of both in the sky represents a miraculous redemption that breaks free from ordinary natural cycles [ביאור שטיינזלץ].

There is a precise distinction in how the fading of these two light sources is described. The sun is spoken of as setting, whereas the light of the moon is described as being gathered or hidden [רש״י, מצודת ציון, ביאור שטיינזלץ]. This difference reflects the physical reality of the moon, which possesses no independent light but only reflects. Its light is gathered and disappears either when the sun illuminating it departs [מלבי״ם], or when the moon aligns with the sun, leaving the earth in darkness [אבן עזרא].

This eternal brightness is guaranteed because its source is divine. Since God Himself serves as the everlasting light, the illumination and the rule it represents will never cease [מצודת דוד]. Consequently, the people of Israel will never again be forced away from this light into another exile [מלבי״ם].

The promise concludes with the complete end of all days of sorrow. There is a deep connection between the presence of light and the end of grief, as it is the nature of a mourner to sit in darkness [אבן עזרא]. Historically, the behavior of the sun has mirrored periods of human tragedy. During times of immense destruction and grief, such as the generation of the Flood or the destruction of the Temple, the sun altered its path or dimmed its glow as an act of mourning, reflecting the idea that one does not shine brightly in the presence of a mourner. However, in the future, when all days of grief are permanently replaced by joy, the sun and moon will never again need to hide their light [אהבת יהונתן].