וְשִׁית־עַל־עָפָ֥ר בָּ֑צֶר וּבְצ֖וּר נְחָלִ֣ים אוֹפִֽיר׃
And lay thy treasure in the dust, And the gold of Ophir among the stones of the brooks;
Rashi on Job
Then you shall make a fortification on the earth By returning to Him, you will establish on the earth strength and fortifications.
Rashi on Job
and on the rocks of the valleys On the lofty rocks in the deep valleys, you shall have a collection of an accumulation of Ophir. This is the treasure of the kings, for they would gather and store gold that came from Ophir.