'Sharpens' in the Bible

“His wrath has torn me and hunted me down,He has gnashed at me with his teeth;My adversary sharpens His gaze and glares [with piercing eyes] at me.

As iron sharpens iron,So one man sharpens [and influences] another [through discussion].

The ironsmith shapes iron and uses a chisel and works it over the coals. He forms the [idol’s] core with hammers and works it with his strong arm. He also becomes hungry and his strength fails; he drinks no water and grows tired.