Parshah Tetzaveh - Exodus 27:20-30:10

And you shall command the children of Israel, that they bring to you pure oil of olives crushed for lighting, to raise an everlasting lamp... from evening to morning (Exodus 27:20-21)

These verses contain a paradox: "everlasting flame" implies a state of perptuality and changelessness; "from evening to morning" implies fluctuating conditions of lesser and greater luminance.

For such is our mission in life: to impart the eternity and perfection of the Divine to a temporal world, and to do so not by negating the world's temporality and diversity, but by illuminating its every state and condition -- from "evening" to "morning" -- with the divine light.

(The Lubavitcher Rebbe)