Job 11:15

For then shalt thou lift up thy face without spot - That is, thy face shall be bright, clear, and cheerful. Thus, we speak of a bright and happy countenance. Zophar undoubtedly designs to show what his appearance would be, contrasted with what it then was. Now his countenance was dejected and sad. It was disfigured by tears, and terror, and long continued anguish. But if he would put away iniquity, and return to God, his face would be cheerful again, and he would be a happy man.

Yea, thou shalt be steadfast, and shalt not fear - The word rendered “steadfast” (מצק mutsaq) is from יצק yâtsaq, to pour, to pour out, and is applied to liquids, or to metals which are fused and poured into a mould, and which then become hard. Hence, it is used in the sense of firm, solid, intrepid. “Gesenius.” Schultens supposes that the reference here is to metallic mirrors, made by casting, and then polished, and that the idea is, that his face would shine like such a mirror. But it may be doubted whether this interpretation is not too refined. The other and more common explanation well suits the sense, and should probably be retained.