Isaiah 48:4

I did this ¹  because I know how stubborn you are. Your neck muscles are like iron and your forehead like bronze. ² 

For I knew how stubborn you were; the sinews of your neck were iron, your forehead was bronze.

"Because I know that you are obstinate, And your neck is an iron sinew And your forehead bronze,

"I know how stubborn and obstinate you are. Your necks are as unbending as iron. You are as hardheaded as bronze.

I know you're a bunch of hardheads, obstinate and flint-faced,

Because I saw that your heart was hard, and that your neck was an iron cord, and your brow brass;

Because I know that you are obstinate, and your neck is an iron sinew and your forehead brass,

Because I knew that you were obstinate, And your neck was an iron sinew, And your brow bronze,

I did this ¹  because I know how stubborn you are. Your neck muscles are like iron and your forehead like bronze. ² 

¹ tn The words “I did this” are supplied in the translation for stylistic reasons. In the Hebrew text v. 4 is subordinated to v. 3.

² sn The image is that of a person who has tensed the muscles of the face and neck as a sign of resolute refusal.