By the breath of God, i.e. by the word of God, as this very phrase is explained, Psalms 33:6; by his will or appointment, to which as the principal cause all these works are ascribed. The breadth of the waters is straitened; the frost dries up the waters in great measure, and bringeth the remainder into a narrower compass, as we see.
Related Commentaries of Job 37:10
Job 37:10
10 By the breath of God frost is given: and the breadth of the waters is straitened.