Complete Commentary on the Whole Bible, by Matthew Henry, at sacred-texts.com
(Job 40:1-5) Job humbles himself to God.
(Job 40:6-14) The Lord reasons with Job to show his righteousness, power, and wisdom.
(Job 40:15-24) God's power shown in Behemoth.
Communion with the Lord effectually convinces and humbles a saint, and makes him glad to part with his most beloved sins. There is need to be thoroughly convinced and humbled, to prepare us for remarkable deliverances. After God had shown Job, by his manifest ignorance of the works of nature, how unable he was to judge of the methods and designs of Providence, he puts a convincing question to him; Shall he that contendeth with the Almighty instruct him? Now Job began to melt into godly sorrow: when his friends reasoned with him, he did not yield; but the voice of the Lord is powerful. When the Spirit of truth is come, he shall convince. Job yields himself to the grace of God. He owns himself an offender, and has nothing to say to justify himself. He is now sensible that he has sinned; and therefore he calls himself vile. Repentance changes men's opinion of themselves. Job is now convinced of his error. Those who are truly sensible of their own sinfulness and vileness, dare not justify themselves before God. He perceived that he was a poor, mean, foolish, and sinful creature, who ought not to have uttered one word against the Divine conduct. One glimpse of God's holy nature would appall the stoutest rebel. How, then will the wicked bear the sight of his glory at the day of judgment? But when we see this glory revealed in Jesus Christ, we shall be humbled without being terrified; self-abasement agrees with filial love.
Those who profit by what they have heard from God, shall hear more from him. And those who are truly convinced of sin, yet need to be more thoroughly convinced and more humbled. No doubt God, and he only, has power to humble and bring down proud men; he has wisdom to know when and how to do it, and it is not for us to teach him how to govern the world. Our own hands cannot save us by recommending us to God's grace, much less rescuing us from his justice; and therefore into his hand we must commit ourselves. The renewal of a believer proceeds in the same way of conviction, humbling, and watchfulness against remaining sin, as his first conversion. When convinced of many evils in our conduct, we still need convincing of many more.
God, for the further proving of his own power, describes two vast animals, far exceeding man in bulk and strength. Behemoth signifies beasts. Most understand it of an animal well known in Egypt, called the river-horse, or hippopotamus. This vast animal is noticed as an argument to humble ourselves before the great God; for he created this vast animal, which is so fearfully and wonderfully made. Whatever strength this or any other creature has, it is derived from God. He that made the soul of man, knows all the ways to it, and can make the sword of justice, his wrath, to approach and touch it. Every godly man has spiritual weapons, the whole armour of God, to resist, yea, to overcome the tempter, that his never-dying soul may be safe, whatever becomes of his frail flesh and mortal body.