Matthew Henry on Job 40:15-24

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.