23 A raging river does not alarm it; it is secure, though the Jordan should surge against its mouth.

Read Job 40:23 Using Other Translations

Behold, he drinketh up a river, and hasteth not: he trusteth that he can draw up Jordan into his mouth.
Behold, if the river is turbulent he is not frightened; he is confident though Jordan rushes against his mouth.
It is not disturbed by the raging river, not concerned when the swelling Jordan rushes around it.