God makes two speeches aimed at Job.
The first is in chapters thirty-eight and thirty-nine. In the first speech, God’s greatness is emphasized by his creative and sustaining powers. The second is in chapters forty and forty-one and it emphasizes God’s strength. These last two chapters introduce us to two creatures, a behemoth (perhaps “hippopotamus”) and a leviathan (perhaps “crocodile”). In the Old Testament, these are creatures made by God (Psalm 104:24-26) and pictured as enjoying God’s world. The word translated “behemoth” occurs a number of times in the Old Testament to refer to “wild animals” (Deuteronomy 28:26; 32:24). Both terms are used in the Old Testament to describe the forces of evil. God is seen to triumph over them (Isaiah 27:1; Psalm 74:14). These terms take on a more graphic and specific meaning here.
These animals stand for a strength and power unmatched by any human, yet both are subdued by God. Behemoth is so powerful that though no one but God can approach it, God can come near (provided he has a sword – 40:19).
The whole purpose of this second speech is to emphasize God has the power to execute His will. John Hartley writes: “If Job could rule the world in justice, he would have to be able to capture Behemoth and subdue Leviathan. . . If Job cannot subdue these mighty creatures, it is inconceivable that he could prove God is treating him unjustly. . . Yahweh is demonstrating to Job that a direct confrontation with himself is a course fraught with danger and certain defeat.”
This is not to say that Job should not have spoken his heart – though Job himself regrets doing so. It is simply, at the end of the day, that Job, exhausted from his tirade against God, rather than getting up and walking away from the Lord, should get up, take the Lord’s hand, and walk with Him.