Job 41:30

²⁸ The arrow cannot make him flee: slingstones are turned with him into stubble.

²⁹ Darts are counted as stubble: he laugheth at the shaking of a spear.

Sharp stones are under him: he spreadeth sharp pointed things upon the mire.

³¹ He maketh the deep to boil like a pot: he maketh the sea like a pot of ointment.

³² He maketh a path to shine after him; one would think the deep to be hoary.

Do read the surrounding verses too, because the context often says more than a single verse.

Compare

BSB: His undersides are jagged potsherds, spreading out the mud like a threshing sledge.
KJV: Sharp stones are under him: he spreadeth sharp pointed things upon the mire.
WEB: His undersides are like sharp potsherds, leaving a trail in the mud like a threshing sledge.
ASV: His underparts are [like] sharp potsherds: He spreadeth [as it were] a threshing-wain upon the mire.
DARBY: His under parts are sharp potsherds: he spreadeth a threshing-sledge upon the mire.
BLB: Beneath him are points of a shard; he spreads out like a threshing sledge upon the mud.

ÅB: På dens buk sitter skarpe skår, den gjør spor i dyndet som etter en treskeslede.
OTB: Hans underdel er som skarpe potteskår;
Han sprer seg som en treskeslede på gjørmen.
B1930: På dens buk sitter skarpe skår, den gjør spor i dyndet som efter en treskeslede.

Isaiah 41:15
Behold, I will make thee a new sharp threshing instrument having teeth: thou shalt thresh the mountains, and beat them small, and shalt make the hills as chaff.
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