Mediaeval spoons were usually made of wood. Spoon was also the name of a chip or splinter of wood and it is likely that is how the table utensils derived their name. It has been a tradition in many countries for wealthy godparents to give a silver spoon to their godchildren at christening ceremonies. That may be the source of the phrase, or it may simply be derived from the fact that wealthy people ate from silver while others didn't. ( source ) When we use the phrase today we are saying that the person being referenced was born into wealth.

This phrase was authored by John Milton in his 1634 work  Comus: A Mask Presented at Ludlow Castle.   I see ye visibly, and now believe That he, the Supreme Good, to whom all things ill Are but as slavish officers of vengeance, Would send a glistering guardian, if need were  To keep my life and honour unassailed.  Was I deceived, or did a sable cloud  Turn forth her silver lining on the night?  I did not err; there does a sable cloud  Turn forth her silver lining on the night,  And casts a gleam over this tufted grove. The phrase morphed throughout the years to the one we use today. Read about its evolution here .  One afternoon I was driving and spotted the silver lining.  So I had to stop and capture it! 

I looked in the mirror today at my hair free of product as the wind was picking it up, rather unattractively I must say, and saw threads of silver.  I know most people try to cover up their threads of silver but I am proud of them...and yes, grateful for them. Hey I've worked hard for these threads that are a symbol of life experience, parenting, marriage, relationships, settling into my own skin, etc. I'm a firm believer in what Proverbs says about these threads of silver . I'm grateful for all of the life that has brought me these threads of silver and I wear them proudly.