They conceive mischief - The meaning of this verse is, that they form and execute plans of evil. It is the characteristic of such men that they form such plans and live to execute them, and they must abide the consequences. All this was evidently meant for Job; and few things could be more trying to a man's patience than to sit and hear those ancient apothegms, designed to describe the wicked, applied so unfeelingly to himself.

They conceive mischief - The figure here is both elegant and impressive. The wicked conceive mischief, from the seed which Satan sows in their hearts; in producing which they travail with many pangs, (for sin is a sore labor), and at last their womb produces fraud or deception. This is an accursed birth, from an iniquitous conception. St. James gives the figure at full length, most beautifully touched in all its parts: When lust hath conceived it bringeth forth sin; and sin, when it is finished, bringeth forth death; James 1:15 (note), where see the note. Poor Job! what a fight of affliction had he to contend with! His body wasted and tortured with sore disease; his mind harassed by Satan; and his heart wrung with the unkindness, and false accusations of his friends. No wonder he was greatly agitated, often distracted, and sometimes even thrown off his guard. However, all his enemies were chained; and beyond that chain they could not go. God was his unseen Protector, and did not suffer his faithful servant to be greatly moved.

They (y) conceive mischief, and bring forth vanity, and their belly prepareth deceit.
(y) Therefore all their vain devises will turn to their own destruction.

They conceive mischief,.... That is, such wicked persons as before described; they meditate sin in their minds, and contrive how to commit it, and form schemes within themselves to do mischief to others:
forth vanity; or sin; for lust when it is conceived bringeth forth sin, and that is vanity, an empty thing, and neither yields profit nor pleasure in the issue, but that which is useless and unserviceable, yea, harmful and ruinous; for sin, when it is finished, bringeth forth death, even death eternal, James 1:14;
and their belly prepareth deceit; their inward part frames and devises that which is designed to deceive others, and in the end proves deceitful to themselves: the allusion is to a pregnant woman, or rather to one who seems to be so, and whose conception proves abortive, and so deceives and disappoints herself and others; see Psalm 7:14.

Bitter irony, illustrating the "unfruitfulness" (Job 15:34) of the wicked. Their conceptions and birthgivings consist solely in mischief, &c. (Isaiah 33:11).
prepareth--hatcheth.