## I have made your face as stubborn as their faces ##
The words "face" and "faces" are used to stand for the people the sentence is about. Alternate translation: "I have made you as stubborn as they are." (See: [[rc://en/ta/man/translate/figs-synecdoche]])
## your brow as hard as their brows ##
The "brow" is the forehead or eyebrow. It used in the same way as "face."
## I have made your brow like a diamond, harder than flint ##
"I have made your brow like the hardest stone, harder than flint."
## flint ##
a stone that is hard enough to start a fire by hitting it with metal or another stone