Job 21:24

In order to refute the argument of [his friends], who wanted to refer everything to [their concept] of divine equity, he shows how they are inferior to him in merits and successes, so that it may clearly appear that in the present state of things the form of justice that they think they understand is lame.

Ver. 23-25. One dieth in his full strength, being rich and prosperous. His inwards are full of fatness, and his bowels are moistened with marrow. And another dieth in the bitterness of his soul, and hath never any wealth.

62. These things being so, who may investigate the secrets of Almighty God, to find out wherefore He permits them so to be? Now to the Elect and the Lost, their life indeed is unlike, but the corruption of the flesh in death is no way unlike.

To show that his riches are not only sufficient, but also superabundant he says, "His bowels are full of fat," for fat is generated by a superabundance of food. Again, he shows his power is based on numerous supports saying, "and his bones are nourished with marrow,": for bones show strength because their strength is supported by the nourishment of the marrow.