The idiom is derived from a line in a John Milton masque (a dramatic homage involving music, dancing, singing, and acting at royal court) called "Comus", written in honour of chastity, that was first performed in 1634 and printed in 1637:

"Was I deceiv'd, or did a sable cloud

Turn forth her silver lining on the night?"

A silver lining is a metaphor for optimism in the English language, meaning that a negative occurrence may have a positive aspect to it.

John Milton (9 December 1608 – 8 November 1674) was an English poet who served as a civil servant for the Commonwealth of England under its Council of State and later under Oliver Cromwell. He is best known for his epic poem “Paradise Lost” (1667), which was written in blank verse.

Milton was a scholar and intellectual who wrote in English, Latin, Greek, and Italian. He achieved international renown within his lifetime, and his celebrated “Areopagitica” (1644), written in condemnation of pre-publication censorship, is among history's most influential and impassioned defences of freedom of speech and freedom of the press.

He introduced new words (coined from Latin) to the English language, and was the first modern writer to employ non-rhymed verse outside of the theatre or translations.

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