This verse is part of an alphabetic acrostic poem about “a wife of noble character” (:10-31). Each verse starts with the succeeding letter of the 22-letter Hebrew alphabet — our verse with the Hebrew letter mem (“M”).
In verse 20, this “wife of noble character” helped the poor and needy. In verse 21, she made sure her own household was well-cared for, especially in inclement weather.
After taking care of others, our verse notes “she makes coverings for her bed.” This godly woman takes care of her own things, too, but the order of priority’s clear — others first, then herself!
We also read “she makes” these things herself. She’s smart, capable and hardworking — consequently, she does have some nice things.
“She is clothed in fine linen” — it’s the term for the imported fine white linen of Egypt. She’s also, “clothed in…purple.”
The ancient’s basically wore wool or linen (from flax), so most clothing was some variation of off-white. It was expensive to dye clothing any color — so note her household was clothed in “scarlet” colored-clothes (:21).
But “purple” was the most expensive of all and is mentioned only here in Proverbs. Famously known as “Tyrian purple” it was a major industry of the coastal Phoenician city of Tyre.
Because of the effort and expense it took to dye anything with this animal-based color (from the murex sea snail), purple came to be considered the color of wealth and royalty. This smart, capable, industrious and spiritual “wife of noble character” (:10) does okay.
She makes caring for others a priority and she has some nice things, too. That’s not surprising.
When God identifies people like her, He continues providing them with good stuff — because He knows they’ll pass it along to bless others, also!