Origin and history of sunlight

"brightness, radiant energy, that which makes things visible," Old English leht (Anglian), leoht (West Saxon), "light, daylight; spiritual illumination," from Proto-Germanic *leukhtam (source also of Old Saxon lioht, Old Frisian liacht, Middle Dutch lucht, Dutch licht, Old High German lioht, German Licht, Gothic liuhaþ "light"), from PIE root *leuk- "light, brightness."

The -gh- was an Anglo-French scribal attempt to render the Germanic hard -h- sound, which has since disappeared from this word.

The meaning "something used for igniting" is from 1680s. The sense of "a consideration which puts something in a certain view" (as in in light of) is from 1680s. As short for traffic light from 1938.

The figurative spiritual sense was in Old English; the sense of "mental illumination" is recorded by mid-15c. Quaker use is by 1650s; New Light/Old Light in church doctrine also is from 1650s.

Omnia, quae sunt, lumina sunt [Scotus Erigena (810?-877?) "All things that are, are light"]

The meaning "person eminent or conspicuous" is from 1590s. A source of joy or delight has been the light of (someone's) eyes since Old English:

Ðu eart dohtor min, minra eagna leoht [Juliana].

Phrases such as according to (one's) lights "to the best of one's natural or acquired capacities" preserve an older sense attested from 1520s. To figuratively stand in (someone's) light is from late 14c. To see the light "come into the world" is from 1680s; later as "come to full realization" (1812). The rock concert light-show is from 1966. To be out like a light "suddenly or completely unconscious" is from 1934.

"the sun as a heavenly body or planet; daylight; the rays of the sun, sunlight," also the sun as a god or object of worship; Middle English sonne, from Old English sunne "the sun," from Proto-Germanic *sunno (source also of Old Norse, Old Saxon, Old High German sunna, Middle Dutch sonne, Dutch zon, German Sonne, Gothic sunno "the sun"), from PIE *s(u)wen-, an alternative form of root *sawel- "the sun."

Old English sunne was fem. (as generally in Germanic), and the fem. pronoun was used in English until 16c.; since then masc. has prevailed, "without necessarily implying personification" [OED].

Under the sun for "anywhere in the world" is by c. 1200 (late Old English had under sunnan). The empire on which the sun never sets (1630) originally was the Spanish, later the British. To have one's place in the sun (1680s) is first in English in a translation of Pascal's "Pensées"; the German imperial foreign policy sense (1897) is from a speech by von Bülow. When the sun is over the foreyard is "noon" at sea, the traditional time of the first serving of the day's first drink.